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PHOTOGRAPHIC  I 
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No.  5.  PHOTOGRAPHY  WITH  EMULSIONS. 

By  Capt.  W.  de  W.  Abney,  R.E.,  F.R.S.  A treatise  on  the  theory  and 
practical  working  of  Gelatine  and  Collodion  Emulsion  Processes.  (Second 
Edition.)  Paper  covers 75 


No.  7.  THE  riODERN  PRACTICE  OF  RETOUCHING. 

As  practiced  by  M.  Piquepe,  and  other  celebrated  experts.  (Ninth 
Edition.)  Paper' covers,  50  cents  ; Library  Edition 75 

No.  8.  THE  SPANISH  EDITION  OF  HOW  TO  MAKE  PICTURES. 

Ligeras  Lecciones  sobre  Fotografia  Dedicados  a los  Aficionados,  Cloth 
bound,  75  cents.  Paper  covers 5° 

No.  12.  HARDWICH’S  PHOTOGRAPHIC  CHEMISTRY. 

A manual  of  Photographic  Chemistry,  theoretical  and  practical.  (Ninth 
Edition.)  Edited  by  J.  Traill  Taylor.  Leatherette  binding 2 00 

No.  13.  TWELVE  ELEMENTARY  LESSONS  ON  SILVER  PRINTING. 

(Second  Edition.)  Paper  covers, 50 

No.  14.  ABOUT  PHOTOGRAPHY  AND  PHOTOGRAPHERS. 

A series  of  interesting  essays  for  the  studio  and  study,  to  which  is  added 
European  Rambles  with  a Camera.  By  H.  Baden  Pritchard,  F.C.S. 
Paper  covers,  50  cents.  Cloth  bound 75 

No.  15.  THE  CHEMICAL  EFFECT  OF  THE  SPECTRUM. 

By  Dr.  J.  M.  Eder.  Cloth  bound,  50  cents.  Paper  covers 25 

No.  16.  PICTURE  MAKING  BY  PHOTOGRAPHY. 

By  H.  P.  Robinson,  author  of  Pictorial  Effect  in  Photography.  Written 
in  popular  form  and  finely  illustrated.  Library  Edition,  $1.00.  Paper 
covers  75 

No.  21.  THE  AMERICAN  ANNUAL  OF  PHOTOGRAPHY  AND 
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No.  22.  PHOTOGRAPHIC  PRINTING  METHODS. 

By  the  Rev.  W.  H.  Burbank.  A Practical  Guide  to  the  Professional  and 
Amateur  Worker.  (Third  Edition.)  Paper  only 75 


No.  23.  A HISTORY  OF  PHOTOGRAPHY. 

Written  as  a practical  guide  and  an  introduction  to  its  latest  developments. 
By  W.  Jerome  Harrison,  F.G.S.,  and  containing  a frontispiece  of  the 
author.  Cloth  bound 1 00 

No.  24.  THE  AHERICAN  ANNUAL  OF  PHOTOGRAPHY  AND 
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Illustrated.  (Second  Edition.)  Paper  (by  mail,  12  cents  additional)  50 
Library  Edition  (by  mail,  12  cents  additional) 1 00 

No.  25.  THE  PHOTOGRAPHIC  NEGATIVE. 

A Practical  Guide  to  the  Preparation  of  Sensitive  Surfaces  by  the  Calotype, 
Albumen,  Collodion,  and  Gelatine  Processes,  on  Glass  and  Paper,  with 
Supplementary  Chapter  on  Development,  etc.,  by  the  Rev.  W.  H.  Burbank. 
Cloth  bound.  Reduced  from  $1.50  to $1  00 


The  S.  & A.  Photographic  Series. 


No.  26.  THE  PHOTOGRAPHIC  INSTRUCTOR  FOR  THE 
PROFESSIONAL  AND  AMATEUR. 

Being  the  comprehensive  series  of  Practical  Lessons  issued  to  the  Students 
of  the  Chautauqua  School  of  Photography.  Revised  and  enlarged.  Edited 
by  W.  I.  Lincoln  Adams,  with  an  Appendix  by  Prof.  Chas.  Ehrmann. 

(Sixth  Edition.)  Paper  covers 1 00 

Library  Edition 1 50 

No.  27.  LETTERS  ON  LANDSCAPE  PHOTOGRAPHY. 

By  H.  P.  Robinson.  Finely  illustrated  from  the  author’s  own  photographs 
and  containing  a Photogravure  frontispiece  of  the  author.  Cloth  bound. 

I 50 

No.  29.  THE  PROCESSES  OF  PURE  PHOTOGRAPHY. 

By  W.  K.  Burton  and  Andrew  Pringle.  A standard  work,  very  complete 
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No.  30.  PICTORIAL  EFFECT  IN  PHOTOGRAPHY. 

By  H.  P.  Robinson.  A new  edition.  Illustrated.  Mr.  Robinson’s  first 
and  best  work.  Cloth  bound 1 50 

No.  32.  PRACTICAL  PHOTO=MICROGRAPHY. 

By  Andrew  Pringle.  Fully  illustrated.  Cloth  bound 2 50 

No.  33.  THE  AHERICAN  ANNUAL  OF  PHOTOGRAPHY  AND 
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Paper  cover  (by  mail,  14  cents  additional) 50 

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No.  34.  THE  OPTICAL  LANTERN. 

Illustrated.  By  Andrew  Pringle.  Paper  covers,  $1.00. 

Cloth  bound I 50 

No.  35.  LANTERN  SLIDES  BY  PHOTOGRAPHIC  METHODS. 

By  Andrew  Pringle.  Paper  covers,  75  cents.  Cloth  bound 1 25 

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Paper  covers  (by  mail,  15  cents  additional) 50 

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Cyclopaedic  Index  for  1891  Annual 10 

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A Text-Book  for  the  Professional  and  Amateur.  By  W.  K.  Burton. 
Paper  covers,  $i.oo.  Library  Edition I 50 

No.  38.  PHOTOGRAPHIC  REPRODUCTION  PROCESSES. 

Illustrated.  By  P.  C.  Duchochois.  Paper  covers,  $1.00.  Cloth...  I 50 

No.  39.  EL  INSTRUCTOR  FOTOGRAFICO 

Paper  covers,  $1.00.  Library  Edition : I 50 

No.  41.  THE  CHEMISTRY  OF  PHOTOGRAPHY. 

By  W.  Jerome  Harrison.  Cloth  bound 3 00 

No.  42.  PICTURE  flAKING  IN  THE  STUDIO. 

By  H.  P.  Robinson.  Paper  Covers,  50  cents.  Cloth  bound  (Library 
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No.  43.  THE  AMERICAN  ANNUAL  OF  PHOTOGRAPHY  AND 
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Edited  by  W.  I.  Lincoln  Adams. 

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bound  (Library  Edition) 1 00 

No.  45.  THE  GRAMMAR  OF  PHOTO-ENGRAVING. 

By  H.  D.  Farquhar.  Illustrated.  The  most  complete  text-book  yet  pub- 
lished on  this  subject.  Price,  in  paper  covers,  $2.00.  Cloth  bound 
(Library  Edition) 2 50 

No.  46.  INDUSTRIAL  PHOTOGRAPHY. 

Illustrated.  By  P.  C.  Duchochois.  Being  a description  of  the  various 
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bound 1 00 

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Paper  covers  (postage  extra,  i 5 cents)  50 

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No.  48.  ARISTOTYPES  AND  HOW  TO  MAKE  THEH. 

Giving  a complete  description  of  the  manufacture  and  treatment  of  Gelatino 
and  Collodio-Chloride  Papers.  By  Walter  E.  Woodbury.  Illustrated. 
Paper  covers,  $1.50.  Library  Edition  2 00 


No.  49.  THE  ENCYCLOPAEDIC  DICTIONARY  OF  PHOTOGRAPHY* 

Containing  over  2,000  references  and  about  400  illustrations.  By  Walter 
E.  Woodbury.  In. preparation. 

No.  50.  THE  AMERICAN  ANNUAL  OF  PHOTOGRAPHY  AND 
PHOTOGRAPHIC  TIMES  ALMANAC  FOR  1895. 

With  over  200  illustrations.  Edited  by  Walter  E.  Woodbury,  Editor  of 
“ The  Photographic  Times.”  Paper  covers,  50  cents  (postage  extra).  Cloth 
bound  (Library  Edition)  (postage  extra,  15  cents) I 00 

No.  51.  THE  PHOTO-GRAVURE. 

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Expert.  Paper  covers,  50  cents.  Cloth  bound  (Library  Edition)  ...  1 00 

No.  52.  THE  PLATINOTYPE:  ITS  PREPARATION  AND  MANIPULATION. 

By  Capt.  W.  de  W.  Abney  and  Lionel  Clark.  Fully  illustrated.  174 
pages 1 25 

No.  54.  PHOTO-ENGRAVING  BY  THE  ENAMEL  PROCESS. 

By  Robert  Whittet.  Fully  illustrated  and  very  complete.  Cloth.  1 00 


No.  55.  INSTANTANEOUS  PHOTOGRAPHY. 

By  Captain  Abney,  c.b.,  r.e.,  d.c.l.,  f.r.s.  Paper  covers 75 

No.  56.  PHOTOGRAPHIC  AMUSEMENTS.  (Second  Edition.) 

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100  illustrations.  Paper  covers.  $1.00.  Cloth 1 50 


No.  57.  THE  AMERICAN  ANNUAL  OF  PHOTOGRAPHY  AND 
PHOTOGRAPHIC  TIMES  ALMANAC  FOR  1897. 

With  250  illustrations.  Edited  by  Walter  E.  Woodbury.  Paper  75 
Cloth 1 25 

For  sale  by  all  dealers  in  Photographic  goods,  booksellers,  and  sent,  post-paid,  on 
receipt  of  price,  by  the  publishers, 

The  Scovill  & Adams  Company  of  N.  Y., 

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Amateur  Photography.  Copy?er 

A Practical  Guide  for  the  Beginner.  By  W.  I.  Lincoln  Adams.  Illustrated.  Paper  covers,  50c.  S 
cloth  bound qq 

Lantern  Slides  and  How  to  Make  Them* 

By  A.  R.  Dresser.  A new  book,  very  complete  and  practical 25 

Photography  at  Night. 

By  P.  C.  Duchochois.  Illustrated.  108  pp.  Paper  covers 100 


The  Knack. 

Written  expressly  to  help  the  beginner  in  perplexity,  reduced  to 26 

Photographic  Lenses ; Their  Choice  and  Use. 

By  J.  H.  Dallmeyer.  A special  edition,  edited  for  American  photographers.  In  paper  covers  25 

The  Chemistry  of  Photography. 

By  Prof.  Raphael  Meldola 2 00 

The  Photographic  Image. 

By  P.  C.  Duchochois.  A Theoretical  and  Practical  Treatise  on  Development.  Paper  covers.. . 1 50 
Cloth  bcund . 2 00 

The  Ferrotyper’s  Guide. 

For  the  ferrotyper,  this  is  the  only  standard  work.  Seventeenth  Edition 75 

The  Photographic  Studios  of  Europe. 

By  H.  Baden  Pritchard,  F.C.S.  Cloth  bound,  $1.00;  paper  covers 50 

History  and  Hand-Book  of  Photography. 

Vvith  seventy  illustrations.  Cloth  bound,  reduced  to 60 


Crayon  Portraiture. 

Complete  instructions  for  making  Crayon  Portraits  on  Crayon  Paper  and  on  Platinum,  Silver  and 
Bromide  Enlargements ; also  directions  for  the  use  of  Transparent  Liquid  Water  Colors,  and  for 
making  French  Crystals.  By  J.  A.  Barhydt.  A new  edition.  Paper  covers,  50c. ; cloth  bound  1 00 

Art  Recreations. 

Ladies’  popular  guide  in  home  decorative  work,  with  a chapter  on  photography.  Edited  by  Marion 
Kemble 1 00 

The  Photographer’s  Book  of  Practical  Formulas. 

Compiled  by  Dr.  W.  D.  Holmes,  Ph.B.,  and  E.  P.  Griswold.  Paper  covers,  reduced  from  75c.  to 
30c. ; cloth  bound,  reduced  from  $1.50  to 60 

American  Hand-Book  of  the  Daguerrotype. 

By  S.  D.  Humphrey.  (Fifth  edition.)  This  book  contains  the  various  processes  employed  in  taking 
heliographic  impressions 25 

Sunlight  and  Shadow. 

A Book  for  Photographers.  Amateur  and  Professional.  By  W.  I.  Lincoln  Adams.  Beautifully  Illus- 
trated. Handsomely  bound.  140  pages.  In  a box 2 50 


LANTERN-SLIDES 

BY 

Photographic  Methods. 


BY 

ANDREW  PRINGLE,  F.R.M.S., 

Ex- President  Photographic  Convention  of  the  United  Kingdom. 
Author  of  “ Practical  Photo- Micrography, ’ ’ ‘‘  The  Optical 
Lantern  f and  J oint-author  of  “ Processes 
of  Pure  Photography etc. 


NEW  YORK: 

THE  SCOVILL  & ADAMS  COMPANY  OF  NEW  YORK, 
60  and  62  EAST  ELEVENTH  STREET. 


Copyright,  1897, 


The  Scovill  & Adams  Company  of  New  York. 


CONTENTS 


Page 

CHAPTER  I. 

Introductory  Remarks, 5 

CHAPTER  II. 

Description  of  a Good  Slide, 7 

CHAPTER  III. 

Characteristics  of  Various  Photographic  Processes,  11 

CHAPTER  IV. 

Apparatus,  - 14 

CHAPTER  V. 

The  Wet  Collodion  Process, - - 21 

CHAPTER  VI. 

Dry  Collodion  Processes, - - - 30 

CHAPTER  VII 

Gelatine  Bromide  Emulsion, 39 

CHAPTER  VIII. 

Gelatine  Bromide  Emulsion,  Continued , 45 

CHAPTER  IX. 

Gelatine  Chloride  Emulsion,  54 

CHAPTER  X. 

Henderson’s  “Argentic  Stain.”  “ Transferotype  ” (Eastman.) 

Collodio-Chloride,  - 57 

CHAPTER  XI. 

Coloring  Lantern  Slides,  - 60 

CHAPTER  XII. 

Masks.  Mounting,  - --  --  --  --  -64 

CHAPTER  XIII. 

Reduction  by  Artificial  Light.  Combination  Printing,  - 66 

Tables  of  Reduction  and  Enlargement, 69 


Lantern^  Slides 

BY  PHOTOGRAPHIC  METHODS. 


CHAPTER  I. 

Introductory  Remarks. 

Lantern-slide  making  is  at  present  almost  wholly  confined 
to  amateurs  in  photography  and  to  a few  firms  who  turn  out 
commercially  enormous  numbers  of  slides,  mostly  in  “ sets.”  So 
far  as  we  know  these  professional  slide-producers  use  either 
photo-mechanical  processes  or  the  wet  collodion  process,  while 
the  amateur  as  a rule  uses  one  or  other  of  the  gelatine  pro- 
cesses, as  gelatine  chloride  or  gelatine  bromide.  The  latter  pro- 
cess is  probably  more  affected  by  the  amateur  than  the  former, 
because  very  frequently  the  slides  have  to  be  made  by  “ reduc- 
tion in  the  camera,”  and  the  chloride  process  is  too  slow  for 
that  system  in  most  cases. 

If  we  had  to  name  the  process  nearest  to  what  we  consider 
the  beau  ideal  of  a process  for  lantern-slide  making  we  should 
probably  name  without  hesitation  one  of  the  mechanical  pro- 
cesses, Woodburytype  for  example.  The  finest  slides  we  have 
ever  seen  have  been  produced  by  that  process,  and  it  would 
certainly  tend  to  make  this  book  more  nearly  a complete 


6 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


treatise  on  our  subject  were  we  to  give  minute  and  practical 
instructions  for  these  processes.  But  we  know  that  long  and 
special  training  is  required  in  order  to  obtain  mastery  over 
these  processes,  and  much  machinery  and  time  are  required ; 
lastly  we  cannot  give  instructions  from  our  own  personal 
experiment,  so  that  it  is  held  preferable  to  omit  rather  than  to 
trifle  with  the  subject.  But  any  one  wishing  to  form  an 
estimate  of  what  a slide  should  be,  will  do  well  to  procure  and 
study  a few  mechanically-produced  slides,  say  in  Woodbury- 
type. 

There  is,  or  was  once,  another  process  held  in  very  high 
estimation  by  cognoscenti  in  slide  matters,  the  Albumen  pro- 
cess. This  process  we  have  worked  with  a fair  amount  of  suc- 
cess, but  we  found  the  trouble,  time,  and  uncertainty  involved 
so  great,  that  we  could  not  occupy  space  in  this  brochure  with 
a full  description  of  this  process.  We  omit  it  all  the  less 
reluctantly  from  the  fact  that  we  never  did  hold  quite  such  a 
high  opinion  of  the  results  on  albumen  as  some  others  did,  and 
we  believe  that  if  the  peculiarities  of  the  albumen  process — 
peculiarities  chiefly  of  color  or  tone — are  desired,  they  can  be 
obtained  by  more  than  one  process  given  in  this  book.  But 
again  we  say  that  a good  subject  for  study  and  imitation  is  an 
albumen  slide  of  the  best  quality,  such  as  some  made  by 
MM.  Ferrier  of  Paris. 

No  good  purpose  is  ever  served  by  superficial  description  of 
any  process  intended  to  yield  practical  results  ; we  shall  there- 
fore describe  minutely  a few  processes  only,  rather  than  skim 
over  many  processes.  W e have  allowed  no  space  in  this  book 
for  guess  work  or  speculation. 


CHAPTER  II. 


Description  of  a (Good  Slide. 

Our  first  and  natural  consideration  is : what  are  the  quali- 
ties of  a perfect  lantern  slide  ? 

To  begin  with  we  have  to  realize  the  nature  and  purpose  of 
a slide.  A slide  is  a ‘positive’  image,  the  highest  lights 
represented  on  the  screen  by  the  illumination  of  the  radiant 
only,  on  the  slide  itself  by  clear  glass.  The  details  are  repre- 
sented on  the  slide,  so  far  as  we  are  concerned,  by  metallic 
silver  reduced  by  light  action  and  chemical  agency  combined, 
from  silver  salts,  and  the  argentic  deposit  is  practically  opaque. 
If  we  have  masses  of  such  metallic  deposit  on  our  slide  we  shall 
certainly  have  masses  of  objectionable  darkness  on  our  screen 
unless  we  take  every  precaution  to  deposit  or  reduce  our  sil- 
ver in  the  finest  possible  state ; in  other  words  our  image 
should  as  nearly  as  possible  be  of  the  nature  of  a stain  rather 
than  of  a stratum  of  pigment.  Further  : however  great  be  the 
brilliance  of  the  radiant  in  our  lantern,  and  however  much  our 
optical  system  may  tend  to  make  the  most  of  our  radiant’s 
brilliance,  there  must  be  a serious  loss  of  light  inseparable 
from  spreading  an  area  of  brilliance  3 inches  in  diameter  over 
an  area  of  (say)  15  feet.  When  we  look  at  an  image  in  silver 
or  in  platinum  on  a paper  print,  the  opacity  of  the  metal  form- 
ing the  image  has  but  little  comparative  effect  on  the  brilliance 
of  the  picture  to  our  eyes,  but  when  we  come  to  look  through, 
and  still  more  when  we  come  to  project  light  through  and 
greatly  enlarge,  our  image,  the  opacity  of  the  image-forming 
substance  makes  a vast  difference  to  the  brilliance  affecting 
our  eyes.  Moreover  we  have  to  take  other  matters  into 
account;  the  almost  inevitable  absorbtion  of  light  by  the 


8 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


screen,  and  the  distance  we  require  to  go  from  the  screen,  and 
so  on.  So  that  while  gradation  is  just  as  essential  to  a slide 
as  to  a paper  print,  the  scale  of  light  requires  in  a slide  to  be 
higher  than  in  a print.  For  a complete  rendering  of  the  scale 
of  light  of  Nature  photography  is  utterly  inefficient ; we  ven- 
ture to  put  it  thus : that  while  in  paper  prints  we  may  endeavor 
to  extend  our  gamut  of  shadows  even  at  the  risk  of  loss  in  our 
gamut  of  lights,  in  a slide  we  must,  perforce,  keep  our  light 
scale  up  even  if  we  shorten  our  shadow  region.  But  the  best 
slide  and  the  best  print  are  those  wherein  we  have  the  longest 
and  the  most  complete  scale.  If  in  our  slide  we  raise  our 
lights  at  the  expense  of  oar  shadows  we  have  the  “midsummer 
snow-scenes”  so  offensive  ; if  we  give  undue  prominence  of 
gradation  to  our  shadow  end  we  run  great  risk  of  having  no 
real  high-lights  at  all.  We  see  it  asserted  in  a book  professing 
to  teach  art  to  photographers  that  a lantern  slide  must  be  out- 
side the  domain  of  art.  The  writer  of  this  book  says  nothing 
whatever  in  defence  of  this  position  of  his,  he  bases  it  simply 
on  his  authority,  which  to  many  minds  will  not  be  enough  to 
condemn  slide  making.  As  a matter  of  fact  an  image  pro- 
jected on  a screen  through  a slide  may  be  just  as  good  or  as 
bad  from  an  artistic  point  of  view  as  a paper  print.  Practically 
such  an  image  is  a print  on  paper,  cloth,  or  in  fresco , but  it 
is  large  and  is  not  persistent.  That  the  ordinary  run  of  slide 
images  are  incorrect  in  “values,”  wanting  gradation,  false  in 
“tonality”  — whatever  that  may  be — is  possible,  but  that  these 
defects  are  inherent  in  and  inseparable  from  slides  is  a ridicu- 
ulous  and  false  assumption. 

A slide  then  must  have  a high  scale  of  light  and  full  grada- 
tion from  its  highest  light  to  its  deepest  shadow.  A large 
mass  of  highest  light  is  just  as  mischievous  in  a slide  as  in  a 
print,  absolute  opacity  is  just  as  much  out  of  place  in  a slide 
image  as  on  a paper  print  image,  and  on  account  of  the  sub- 
stantial nature  of  the  slide  image  there  is  greater  danger  of 
dense  opacity  in  a slide  than  in  a print,  for  the  print  is  always 
illuminated  to  our  eyes  by  more  or  less  reflected  light.  If  high 
lights  preponderate  in  our  slide  the  image  will  be  of  the  brilliant 


LANTERN-SLIDES  BA  PHOTOGRAPHIC  METHODS. 


9 


type ; if  shadows  preponderate,  we  shall  have  a subdued 
slide ; but  the  gradation  must  be  in  both.  A very  common 
fault  indeed  in  slide-making  is  to  produce  a slide  of  an  Interior 
on  a scale  of  light  precisely  coincident  with  the  scale  of  an 
open  landscape  ; this  must  be  wrong,  yet  many  slide-makers 
congratulate  themselves  on  such  achievements  which  are  not 

O 

only  abominable  but  easy.  Probably  photographers  are  encour- 
aged in  this  vandalism  by  the  approbation  of  an  unthinking 
and  uneducated  public  which  applauds  a ‘clear’  slide  whatever 
its  other  qualities  may  be,'  but  it  is  time  that  we  photographers 
should  correct  this. 

When  half-tone  is  in  abnormal  preponderance  we  have 
either  a “ washed-out  ” image,  or  in  aggravated  cases  a scale  of 
light  so  low  as  to  amount  to  “ fog.”  This  is  the  converse  fault 
to  “summer  snow,”  and  equally  baneful;  it  is  perhaps  the 
commonest  fault  with  beginners,  and  arises  in  nearly  all  cases 
from  faulty  technique,  or  a bad  negative. 

The  next  attribute  of  a slide  is  that  of  color  or  “ tone,”  or 
as  it  is  sometimes  called  “ medium.”  The  color  of  image  most 
frequently  seen  is  a sort  of  cold  slaty  blue,  It  is  the  tone  most 
easily  produced,  and  most  objectionable  if  we  except  the  dirty 
“ bottle-green,”  which  luckily  is  not  so  common  as  it  used  to 
be  when  plate-makers  and  plate-users  were  less  skillful.  This 
slate  color  is  seen  in  many  amateurs’  iron-developed  slides,  and 
in  numbers  of  commercial  slides  where  the  platinum-toning 
process  has  been  underdone,  or  done  on  unsuitable  positives. 
Far  preferable  to  this  is  a good  warm  blue-black,  such  as  is 
produced  by  the  wet  process,  used  properly,  or  by  gelatine 
processes  under  the  best  conditions  of  exposure  and  iron- 
development,  or  quinol-development.  But  we  yearn  after 
warm  tones,  such  as  can  be  produced  easily  with  dry  collodion, 
with  gelatine  chloride,  and  with  “Argentic  Stain,”  (see  p.  57) 
and  less  easily  with  gelatine  bromide.  We  believe  not  only 
that  the  warm  tones  are  required  for  perfect  slides,  but  that 
the  photographic  world  is  entirely  of  our  opinion ; the  public 
will  soon  follow.  The  albumen  slides,  so  much  admired,  are 
of  warm  tone,  the  mechanical  slides  are  still  warmer  and  some 


10 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


of  our  most  applauded  slide-makers  affect  warmth  and  eschew 
blues.  We  are  referring  wholly  to  pictorial  subjects  at  present ; 
slides  purely  scientific,  as  astronomical,  microscopic,  and  the 
like,  are  probably  better  rendered  in  cold — but  not  blue — 
tones.  We  shall  lay  down,  then,  a warm  tone  as  essential  to  a 
perfect  slide  ; failing  tints  tending  to  red,  we  must  content  our- 
selves with  a thorough  good  engraving-black,  such  as  one 
illustrious  amateur  knows  how  to  produce,  but  very  few  other 
workers  in  this  field. 

To  sum  up.  A slide  to  be  perfect  must  have  : (1)  A high 

scale  of  lighting.  (2)  A continuous  scale  of  gradation.  (3) 
A pleasing  tone.  To  put  it  otherwise.  A slide  must  have : 
(1)  Clear  highest  lights.  (2)  Secondary  lights  well  furnished 
with  detail.  (3)  Middle  tones.  (4)  Transparent  shadow 
details.  (5)  A good  general  color  of  image. 

So  much  for  the  photographic  qualities  of  a slide ; we  have 
others  to  consider.  The  size  of  a slide  plate  is  three  and  one- 
quarter  inches  square,  there  is  no  reason  for  changing  this  size, 
or  for  adopting  any  other.  But  the  frame  of  our  picture — 
the  “mask,”  technically — requires  consideration.  Why  we 
should  adopt  for  slides  shapes  and  proportions  practically 
unknown  in  any  other  branch  of  graphic  art  is  a mystery,  and 
the  sooner  we  alter  this  practice  of  circular  and  “square- 
cushion  ” masks  the  better.  (See  remarks  in  Chapter  XII.) 


CHAPTER  III. 


Characteristics  of  Various  Photographic  Processes. 

There  is  a slight  risk  of  misconception  attached  to  this 
chapter,  and  it  will  be  well  to  point  out  where  the  risk  lies. 
We  propose  to  point  out  what  may  be  taken  as  the  salient 
features  of  each  process  for  good  or  for  bad,  but  the  reader  is 
not  intended  to  understand  that  an  observed  characteristic  or 
tendency  is  necessarily  the  character  or  result  of  any  process. 
Any  of  the  processes  may,  under  certain  conditions,  show  all 
the  characteristics  and  results,  good,  bad  and  indifferent, 
mentioned  by  us. 

The  quality  of  clearness  in  the  highest  lights  is  certainly 
most  easily  obtained  by  the  collodion  processes ; these  are 
followed  more  or  less  closely  in  order  by  the  gelatine-chloride 
process,  the  gelatine-bromide  process  standing  last  in  this 
respect. 

The  quality  of  opacity  in  juxtaposition  with  absolute 
clearness , which  is  so  valuable  in  such  slides  as  are  copies  of 
engravings,  is  most  easily  obtained  by  collodion  with  or 
without  intensification,  by  gelatine-chloride,  and  then  by 
gelatine-bromide  used  in  a special  manner. 

A long  scale  of  gradation  is  a branch  of  excellence  wherein 
gelatine-bromide  stands  first,  the  other  processes  we  can  not 
place  in  any  order  of  merit,  except  that  w^e  are  inclined  to 
place  wret  collodion  last.  The  qualities  of  half-tone  trans- 
parence of  shadoio  may  be  taken  as  synonymous  or  equivalent, 
and  may  follow  the  same  order,  but  of  all  the  transparent 
shadows  we  have  ever  seen  produced  by  pure  photography,  none 
could  match  with  those  produced  by  Mr.  A.  L.  Henderson’s 
“ argentic  stain,”  which  we  shall  certainly  mention  later. 


12 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


Warmth  of  tone  may,  to  a certain  extent,  be  achieved  by 
any  of  our  processes ; but  warmth  combined  with  excellence 
in  other  respects  is  certainly  the  province  of  dry  collodion. 
With  gelatine  organo-chloride  plates  we  can  with  ease  produce 
a very  long  range  of  colors  from  scarlet  to  the  coldest  blue,  but 
there  is  a something  lacking  in  the  other  qualities  of  plates 
treated  so  as  to  give  the  warm  tones.  When  first  Mr.  Cowan 
showed  us  his  grand  results  in  this  line  we  expected  that  herein 
lay  the  future  of  slide-production,  but  somehow  the  slides  did 
not  on  the  screen  come  up  to  our,  and  we  presume  to  public, 
expectation,  for  very  few  slides  of  this  kind  are  ever  seen, 
though  to  our  knowledge  they  are  not  difficult  to  produce. 
Wet  collodion  slides  may  be,  and  sometimes  are,  “toned”  to 
really  warm  colors,  but  a suspicion  as  to  their  permanency  is 
afloat,  and  justly  or  unjustly,  the  dog  has  acquired  a bad  name. 
Under  the  head  of  gelatine-bromide,  careful  directions  shall  be 
given,  the  result  of  much  experiment,  for  the  production  of 
warm  tones;  but  it  should  be  clearly  understood  that  if 
warmth  were  our  prime  and  only  consideration  we  should  use 
dry  collodion. 

Next,  as  to  our  purpose  and  our  conveniences.  If  our 
purpose  is  simply  to  make  lantern-slides,  as  good,  as  rapidly, 
and  as  cheaply  as  possible,  the  plain  course  is  to  take  quarter- 
plate  negatives,  and  make  contact-slides  on  gelatine-chloride,  or 
on  collodio-bromide. 

So,  too,  if  we  have  at  command  only  limited  time,  specially 
if  the  time  be  limited  to  evening,  we  are  almost  bound  to 
make  our  slides  by  contact,  and  so  we  should  use  gelatine- 
chloride  or  collodio-bromide.  But  if  we  have  a stock  of 
large  negatives,  or  if  we  wish  to  make  large  negatives  and  from 
them  slides  by  reduction,  these  two  processes  are  put  out  of  the 
field  by  the  more  rapid  gelatine  bromide  or  wet  collodion,  and 
in  fact  the  exposure  tor  reduction  on  wet  collodion  by  artificial 
light  may  almost  be  put  aside  when  we  consider  that  we  have 
gelatine-bromide  more  rapid,  especially  in  ordinary  artificial 
light,  and  better  in  certain  important  qualities  already  cited. 
But  if  daylight  is  at  our  disposal,  and  scientific  slides  our 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


13 


object,  the  wet  collodion  process  has  claims  not  lightly  to  be 
set  aside. 

We  have  next  to  consider  what  may  fairly  be  called  the  best 
all-round  process.  The  author  ventures  to  pronounce  in  favor 
of  gelatine-bromide ; it  is  rapid,  but  not  too  rapid  for  contact 
work ; properly  used  it  yields  highest  lights  practically  unim- 
peachable, it  is  remarkable  for  gradation,  and  it  will  yield 
either  a good  cold  tone  or  under  the  best  conditions  a very  fine 
warm  tone.  And  the  writer  will  further  venture  to  recom- 
mend those  who  have  but  limited  time,  limited  purse,  and 
limited  intentions,  to  work  at  the  gelatine-bromide  process  till 
perfection  is  attained,  as  it  almost  certainly  will  by  practice 
and  care  be  attained.  Those,  on  the  other  hand,  who  have 
opportunity  and  desire  for  a course  of  most  interesting  experi- 
ments, and  a succession  of  most  beautiful  results,  are  advised 
to  follow  the  matter  of  this  little  book  not  only  with  their 
eyes  and  minds,  but  with  their  hands. 


CHAPTER  IV. 


Apparatus — Contact-Printing.  Reduction. 

We  require  for  contact-printing  an  ordinary  printing-frame, 
an  article  well  known  to  every  photographer.  If  we  are  going 
to  make  a contact  slide  from  part  of  a quarter-plate  negative, 
we  should  use  a quarter-plate  frame  with  ledges  about  one- 
eighth  of  an  inch  wide  upon  which  the  negative  may  rest. 
These  ledges  will  act  as  masks  for  two  sides,  or  possibly  three, 
of  the  slide-plate.  Sometimes,  if  the  margins  of  the  slide- 
plate  are  not  protected  from  the  light  passing  through  the 
negative,  a certain  amount  of  blurring  will  be  found  at  the 
edge  of  the  slide,  this  area  of  blur  may  or  may  not  be  hidden 
by  the  mask  used  in  mounting  the  slide.  Anyhow  it  should 
be  avoided.  Some  persons  place  between  the  negative  and 
the  slide-plate  in  the  frame  a mask  with  a suitable  aperture, 
and  if  the  mask  paper  be  very  thin  and  of  a non-actinic  color 
the  result  is  perfect,  especially  if  strong  pressure  be  brought 
to  bear  on  the  back.  Sharpness  must  not  be  endangered 
in  a lantern  slide,  for  when  enlarged  on  a screen  the  image  is 
not  likely  to  offend  the  most  naturalistic  eye  by  over- sharpness. 
If  the  negative  and  printing  frame  are  lantern-size  there  is  no 
difficulty.  As  a rule  it  will  be  found  incorrect  to  make  a con- 
tact-slide of  any  portion  out  of  the  middle  of  a much  larger 
negative,  the  image  on  the  screen  always  looks  “ uncomfort- 
able.” 

A standard  light  is  a matter  of  importance,  especially  to  the 
beginner.  The  following  devices  have  proved  satisfactory  in 
our  hands : A “ Regulator  gas  burner.”  A government 
standard  candle  allowed  to  burn  for  at  least  three  minutes  before 
exposure  is  made.  A certain  oil  lamp  having  above  its  flame 
an  attached  arm  up  to  which  the  flame  is  always  raised.  A 


L AK TERN- SLIDES  BY  PHOTOGRAPHIC  METHODS. 


15 


certain  length  of  a certain  make  of  magnesium  wire  or  ribbon. 
This  wire  or  ribbon  if  kept  for  some  time  ceases  to  be  a stand- 
ard on  account  of  the  action  of  the  air  upon  it.  This  may  be 
rectified  practically  by  pulling  the  ribbon  or  wire  several 
times  between  the  folds  of  a piece  of  sand  or  emery  paper 
held  between  finger  and  thumb. 

Equally  important  to  a standard  light  is  a standard  distance 
from  radiant  to  receiving  surface.  Looseness  in  the  matter  of 
distance  may  lead  to  serious  errors.  The  so-often  quoted  law 
must  be  kept  in  mind : the  intensity  of  light  varies  inversely  as 
the  square  of  the  distance  from  radiant  to  recipient,  provided 
the  rays  be  not  interfered  with  in  transit,  as,  for  instance,  by  a 
paralleliser  or  condenser.  Thus  if  the  proper  exposure  be  ten 
seconds  when  the  slide  plate  is  held  twelve  inches  from  the 
radiant,  the  corresponding  exposure  at  eighteen  inches  will  be  : 

123  : 18s  ::  10  : 23  seconds  approximately.  Again  suppose 
that  we  have  a fixed  exposure  of  ten  seconds  at  eighteen 
inches,  but  by  mistake  increase  the  distance  to  twenty  inches 
we  make  an  error  in  exposure  of  nineteen  per  cent,  of  the 
proper  exposure  ; or  if  x be  1 00  seconds  at  eighteen  inches, 

124  seconds  (nearly)  will  be  required  to  produce  the  same  effect 
at  twenty  inches.  Our  habit,  therefore,  ought  to  be  to  place 
the  radiant  at  a certain  marked  spot,  and  to  have  marked  on  the 
table  a scale  of  inches,  or  of  short  lengths,  such  as  three  inches, 
from,  say,  nine  inches  to  thirty  inches.  A piece  of  cord  wdth 
knots  at  various  distances  may  be  found  equally  useful ; and 
when  time  is  an  object,  or  the  cost  of  magnesium  ribbon  a 
consideration,  circles  may  be  drawn  with  radii  from  four  and 
one-half  to  fifteen  inches,  a small  spirit  lamp  being  placed  over 
the  centre  of  these  concentric  circles  and  the  length  of  magne- 
sium being  ignited  and  held  at  the  spirit  lamp.  By  this 
method  a number  of  plates  can  be  exposed  at  equal  or  unequal 
distances  simultaneously.  The  ribbon  or  wire  must  of  course 
be  held  in  a pair  of  pincers  or  forceps. 

u N on-actinic  ” or  “ dark-room  ” lanterns  are  often  made  with 
a door  or  windows  which  can  be  opened  at  will  so  that  the 
light  inside  may  be  used  as  radiant  for  giving  the  exposure. 


16 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


Reduction  in  the  Camera . If  our  negative  is  larger,  or  the 
part  of  it  we  wish  to  reproduce  is  larger  than  a slide  plate,  we 
mnst  u reduce  ” the  size  to  the  required  dimensions  ; in  fact,  we 
mnst  make  a small  positive  photograph  of  our  negative.  The 
mechanics  of  this  operation  are  almost  as  simple  as  those  for 
contact-printing.  The  requirements  are  : Even  illumination 

of  the  negative;  means  for  holding  the  negative  and  slide 
plate  parallel  to  each  other ; a lens  to  effect  the  reduction  ; a 
light-tight  box  to  hold  the  sensitive  plate  so  that  no  light-rays 
shall  reach  the  plate  except  such  as  pass  through  the  negative 
and  the  lens  ; “ motions,”  whereby  the  distances  from  negative 
to  lens  and  from  lens  to  sensitive  plate  can  be  altered ; and  a 
certain  amount  of  traverse,  horizontal  and  vertical,  whereby 
the  lens  can  be  placed  opposite  to  various  parts  of  the  surface 
of  the  negative.  If  we  intend  to  use  one  size  only  of  negative, 
and  to  reduce  the  whole  of  its  image  each  time,  our  apparatus 
may  be  even  simpler,  for  we  shall  then  require  no  “ traverse” 
and  very  little  focusing  motion,  and  no  alteration  of  distance, 
once  fixed,  between  negative  and  lens. 

The  simplest  arrangement  we  ever  saw  consisted  in  hanging 
or  placing  on  a ledge  in  a window  having  no  trees  nor  other 
objects  within  many  yards  outside,  the  negative  to  be  copied. 
A camera  on  a studio  stand  was  then  wheeled  up,  squared  and 
focused,  and  a wet  plate  exposed  in  the  camera.  The  results, 
so  far  as  the  apparatus  was  concerned,  left  nothing  to  be 
desired  ; but  if  one  has  many  different  size  negatives  to  reduce, 
or  wishes  to  reduce  now  one  part  now  another,  there  must  be 
a little  trouble  about  the  centering  and  squaring  so  often. 

Nothing  can  well  be  simpler  than  the  following,  Fig.  1 : 


A B 


Fig.  1. 

A is  a framework  carrying  the  negative,  B a little  camera 
of  the  plainest  construction,  fitted  with  a rack  and  pinion 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS.  IT 

focusing  arrangement  and  having  a front  carrying  a lens  and 
traversing  in  both  directions.  If  we  intend  always  to  include 
in  our  slide  the  whole  of  the  subject  shown  on  the  negatives 
there  is  no  need  for  traverses ; and  the  traverse  can  be  effected 
equally  well  on  the  base  board  C D,  or  on  the  block  on  which 
the  camera  is  raised,  or  the  frame  carrying  the  negative  may 
traverse,  it  is  a matter  of  choice  if  it  is  necessary  at  all.  The 
negative  frame  may  advance  and  recede  along  C D in  ayy 
convenient  way,  between  runners  or  along  a longitudinal  slot 
in  C D,  or  the  block  on  which  B rests  may  move  in  like  man- 
ner. The  negative  in  A and  the  plate  in  B must  always  be 
parallel.  A should  be  so  arranged  that  whatever  size  of  nega- 
tive be  used  its  centre  should  always  be  in  the  optical  axis  of 
the  lens  in  B at  the  normal  position;  for  this  the  best  system 
is  to  make  A consist  of  “ nested  carriers.’  The  amount  of 
reduction  is  regulated  by  the  distance  from  A to  B,  the  focus 
of  the  lens  is  adjusted  by  the  focusing  arrangement  of  B. 

If  this  entire  system  can  be  pointed  at  a clear  sky  the  light- 
ing of  A will  be  even,  but  if  clouds,  or  trees  or  houses  are 
behind  A the  lighting  should  be  modified  either  by  an  angled 
reflector,  which  must  be  larger  than  the  negative,  or  by  a 
sheet  of  ground  glass  or  tissue  paper  an  inch  or  two  behind, 
and  parallel  to,  and  as  large  as,  the  negative.  The  reflector, 
if  one  is  used,  should  be  white  but  not  glossy ; nothing  is 
better  than  a sheet  of  fine  white  filter  or  blotting  paper. 
Mirrors,  opals  and  such  shiny  surfaces  are  inferior  to  matt 
surfaces  theoretically  and  practically.  The  best  angle  for  the 
re&ector  will  be  found  by  experiment,  and  the  more  it  is 
angled  and  the  further  it  is  from  the  negative  the  larger  it 
will  require  to  be.  The  ground  glass  or  tissue  paper  arrange- 
ment may  be  as  fine  in  “ grain”  as  is  consistent  with  diffusion 
of  the  light ; if  there  are  dark  objects  anywhere  close  behind 
the  negative,  as  trees  or  houses,  the  effect  will  soon  be  noticed, 
if  not  in  the  camera  certainly  on  the  slide.  The  entire  system 
of  Fig.  1 should  always  point  to  the  North  if  such  an  aspect 
is  available,  that  is  to  say,  the  negative  should  be  North  of 
the  camera;  if  the  sun  shines  directly  or  by  reflection  from  a 
mirror  on  the  negative,  mischief  may  be  expected. 


18 


LANTERN- SLIDES  BY  PHOTOGRAPHIC  METHODS. 


It  is  not  perhaps  essential  but  it  is  certainly  advisable  to 
prevent  light  from  intervening  between  negative  and  lens, 
except  such  light  as  has  passed  through  the  former.  Between 
A.  and  B.,  then,  an  opaque  cloth  may  stretch,  supported  if 
necessary  on  standards.  Or  a box  with  the  ends  knocked  out 
may  suffice. 

A handy  carpenter  can  make  an  arrangement  such  as  Fig.  1 
in  an  hour,  if  paid  by  the  piece,  and  provided  with  the  camera 
and  carriers. 

Fig.  2 was  made  by  the  writer  in  10  minutes,  or  thereabout, 
he  uses  no  other  arrangement  and  has  not  a fault  to  find 
with  it. 


The  arrangement,  as  will  be  seen  at  once,  consists  of  two 
cameras  stuck  face  to  face  ; the  cut  (Fig.  2)  shows  all  the 


LANTERN  SLIDES  BY  PHOTOGRAPHIC  METHODS. 


19 


‘making’  needed  on  the  part  of  the  writer.  A piece  of  wood, 
chosen  grooved  for  convenience  of  making  sliding  runners,  was 
screwed  to  the  front  of  a little  quarter  plate  camera,  useless 
for  outdoor  work  from  age  and  infirmity.  An  oblong  hole 
was  made  in  the  middle  of  the  piece  of  wood  ; the  screwed-on 
front  was  run  into  the  runners  in  the  front  of  the  large  camera 
which  also  was  superannuated,  and  superseded  on  account  of 
its  weight.  The  lens  was  screwed  into  its  flange  in  the  small 
camera  through  the  hack  of  the  large  camera,  and  the  appar- 
atus was  complete.  A wet-plate  slide  opened  back  and  front 
holds  the  negative,  carriers  or  ‘kits’  hold  different  sized  nega- 
tives ; distance  from  negative  to  lens  is  regulated  by  the  rack 
and  pinion  of  the  large  camera,  focussing  is  adjusted  by  the 
small  camera,  traverse  in  both  directions  is  attained  by  the 
front  of  the  large  camera  or  in  extraordinary  cases  by  pulling 
out  the  slide  carrying  the  negative.  Thus  the  apparatus  is 
complete  and  universal.  Every  one  has  the  camera  in  which 
he  took  the  original  negatives  ; this  camera  is  in  no  way  hurt 
or  altered  by  the  attachment  of  the  little  camera ; and  the  lat- 
ter requires  absolutely  no  motion  except  the  invariable  one  for 
focusing,  so  that  a mere  toy  camera  is  good  enough.  Ground 
glass,  or  angled  reflector  is  as  before. 

The  arrangements  given  above  are  not  makeshifts,  we  never 
would  use  a makeshift,  still  less  recommend  one.  We  do  not 
believe  that  a better  arrangement  could  be  devised  or  made  at 
any  expense  whatever,  and  the  reader  will  own  our  apparatus 
is  simple  enough. 

In  most  cases  it  is  well,  in  many  it  is  necessary,  to  cant  the 
whole  apparatus  more  or  less ; this  is  easily  managed,  and 
requires  no  instruction.  In  Fig.  2 is  shown  the  head  of  a 
cheap  studio  stand. 

The  lens  used  should  be  rectilinear,  and  should  be  of  such 
focal  length  and  construction  as  to  cover  at  a reasonable 
aperture  the  whole  of  a 3^  inch  plate  sharply.  There  is  no 
need  of  a lens  of  more  than  4 inches  solar  focal  length  ; the 
one  we  invariably  use  is  a “ rectilinear  stereo,”  of  under  4 
inches  focal  length,  made  by  Dallmeyer,  and  used  almost 
always  at  yl. 


20 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


Some  kind  of  ocular  is  required  to  adjust  tlie  focus  on  the 
ground-glass  of  the  little  camera,  for  the  details  are  often  too 
small  for  the  eye  to  appreciate  critically  in  the  very  subdued 
light  forming  the  image  on  the  screen.  The  article  known  as 
a Ramsden  eye-piece,  magnifying  about  three  times,  is  what  we 
use.  This  glass,  and  all  used  in  a similar  way,  must  itself  be 
focused  on  the  inner  side  of  the  focusing  screen ; the  metal 
cell  carrying  the  glass  being  in  contact  with  the  outer  side  of 
the  focusing  screen.  The  “ grain  ” of  the  ground-glass  is  a 
very  difficult  surface  on  which  to  set  the  Ramsden  ; but  if  a 
fly’s  wing  or  some  such  object  be  temporarily  fixed  to  the  front 
of  the  ground-glass,  and  viewed  from  the  opposite  side,  the 
ocular  can  be  easily  and  accurately  set  to  focus.  It  will  be 
found  very  convenient  to  put  in  the  centre  of  the  ground-side 
of  the  focusing  screen  a pafcli  of  oil,  or  to  cement  to  it  a 
round  microscopic  66  cover-glass  ’*  with  Canada  balsam.  This 
clear  spot  may  be  about  half  an  inch  to  an  inch  in  diameter. 


CHAPTER  Y. 


The  Wet  Collodion  Process. 

Full  and  minute  instructions  for  every  operation  connected 
with  the  process  which  for  years  occupied  the  attention  of  every 
photographer  in  the  world  could  not  very  well  be  given  in  so 
small  a space  as  is  at  our  command.  For  the  general  features 
of  the  process  and  the  general  method  of  manipulation  the 
reader  may  refer  to  any  book  with  any  pretence  of  complete- 
ness in  the  treatment  of  photographic  processes.  In  particular, 
a sufficiently  full  and  careful  digest  of  the  operations  will  be 
found  in  “ Processes  of  Pure  Photography  ” in  the  production 
of  which  the  present  author  had  a hand,  in  collaboration  with 
Prof.  Burton,  C.  E.  (Hew  York,  The  Scovill  & Adams  Co., 
1889.)  What  we  propose  to  do  here  is  to  give  a correct  but 
cursory  resume  of  the  process,  emphasizing  those  points 
demanding  or  deserving  special  notice  from  those  using  the 
process  for  slide-making. 

We  have  already  pointed  out  the  good  and  the  doubtful 
qualities  of  this  process  for  our  purpose,  we  now  wish  to  show 
wherein  lie  the  special  dangers,  and  the  means  of  attaining  the 
special  excellencies.  In  general  the  dangers  are  those  arising 
from  atmospheric  impurities  and  chemical  carelessness.  The 
plate  is  wet  or  damp  from  beginning  to  end,  and  is  not  like  a 
dry  plate  submerged  in  a liquid  all  the  time  while  the  critical 
chemical  operations  are  going  on,  for  the  wet  plate  is  taken 
out  of  the  bath,  put  into  a slide,  and  carried  about  rooms  in  a 
state  most  apt  to  catch  dust ; and  moreover  the  silver  nitrate, 
both  in  the  bath  and  on  the  plate,  is  highly  sensitive  to 
organic  contamination.  The  greatest  care  is  therefore  nec- 
essary to  avoid  dust  at  every  stage,  and  to  banish  from  the 


22 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS 


vicinity  every  trace  of  suspended  organic  matter.  The  very 
cleaning  of  the  glass  plate  is  a function  the  gravity  of  which 
the  modern  dry  plate  man  can  barely  conceive.  Organic  mat- 
ter produces  veil  or  fog  and  so  destroys  the  strongest  point  in 
favor  of  this  process,  while  dust  adhering  to  the  film  is  fatal  to 
the  mechanical  perfection  of  the  result. 

The  glass  used  should  be  thin,  flawless,  and  flat,  and  the 
size  should  be  larger  each  way  than  the  slide  is  to  he.  A suita- 
ble size  may  he  4 inches  square,  or  4 will  probably  be  more 
convenient  as  one  dimension  of  a quarter-plate.  A square 
quarter-plate  camera  will  then  he  required,  or  at  least  a square 
dark  slide.  The  necessary  image  will  he  only  about  3 inches  in 
its  longest  dimension.  If  the  glass  is  new,  a good  rubbing, 
first  with  alcohol  and  ammonia  equal  parts  with  a little  tripoli 
added,  will  remove  from  the  surface  dirt  of  a greasy  nature. 
After  this  it  requires  a strenuous  polishing  with  a perfectly 
clean  chamois  leather,  not  washed  in  soda.  If  the  plate  has  been 
used  previously  it  should  be  soaked  for  an  hour  in  nitric  acid 
and  water  equal  parts,  then  well  washed  under  a tap,  then 
cleaned  and  polished  as  before.  The  collodion  should  not  be 
quite  freshly  iodised,  still  less  should  it  be  very  old,  and  the 
proportion  of  bromide  should  be  kept  down,  while  iodide  may 
be  in  excess  of  the  usual  proportion  for  landscape  or  portrait- 
ure. The  plate  held  on  a scrupulously  clean  holder,  rather 
than  in  or  on  the  fingers,  is  to  be  coated  with  collodion  in  the 
time-honored  fashion,  steadily,  evenly,  and  entirely  sheltered 
from  dust.  The  surplus  collodion  should  not  be  returned  to 
the  bottle  whence  it  came,  but  to  a second  ; and  certainly  there 
must  be  no  grinding  of  the  plate  on  the  mouth  of  the  bottle. 
A proper  collodion  pourer  should  be  used,  ordinary  bottles 
lead  to  frequent  mischief.  The  corner  at  which  the  surplus 
runs  off  is  to  be  kept  downwards,  but  the  plate  while  the  collo- 
dion is  dripping  must  be  very  steadily  rocked  sidewise  to 
ensure  even  coating  and  absence  of  ridges.  When  the  drip- 
corner  is  “tacky”  and  shows  an  impression  of  the  finger-skin 
that  may  be  made  to  touch  it,  the  plate  is  ready  to  be  put  into 
the  silver  bath.  The  collodion  may  take  from  20  to  50  or  60 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS.  23 

seconds  to  set  as  above,  according  to  temperatnre.  No  part 
of  the  film  must  be  dry  when  the  plate  is  immersed  in  the  sil- 
ver bath. 

The  “ silver  ” or  “ sensitizing  ” bath  is  very  easy  to  make, 
but  not  so  easy  to  keep  in  order ; so  it  is  well  to  make  two 
separate  quantities  of  it  at  first,  and  to  use  one  portion  while 
the  other  is  allowed  to  rest  or  is  under  repair,  for  the  bath 
needs  rest  and  repair  occasionally.  Distilled  water  (not  con- 
densed, however,  from  greasy  engine  valves),  should  be  used, 
or  rain  water  caught  directly  in  a clean  porcelain  vessel,  or 
ordinary  pure  water  treated  with  a crystal  or  two  of  silver  nit- 
rate and  kept  for  some  days  in  a bright  light.  Rain  water 
should  be  treated  in  the  same  way.  A good  strength  for  the 
bath  will  be  : thirty-five  grains  of  re-crystallized  silver  nitrate 
to  water  one  ounce.  For  lantern  slides  we  recommend  a “dip- 
ping bath  ” in  preference  to  a flat  dish  for  sensitizing  the 
plates,  as  the  former  is  likely  to  secure  greater  immunity  from 
dust  on  the  plate.  (See  “ Processes.”)  The  dipping  bath  will 
require  a larger  original  bulk  of  silver  solution,  but  the  larger 
quantity  will  keep  longer  in  working  order.  The  bath  must 
be  slightly  iodized  before  the  serious  work  begins  ; to  do  this, 
coat  a plate  with  iodized  collodion  and  leave  it  in  the  bath 
solution  for  some  hours,  or  add  a crystal  of  potassium  iodide 
directly  to  the  bath. 

The  plate  coated  with  collodion  is,  when  “ set,”  immersed 
steadily  and  without  stoppage  or  hesitation  in  the  bath,  care 
being  taken  that  the  fingers  do  not  touch  the  solution,  but  only 
the  dipper  or  a silver  hook  made  for  the  purpose ; and  after 
resting  in  the  solution  for  one  minute  it  is  raised  out  of  the 
solution  for  a couple  of  seconds  and  let  down  again,  and  it  may 
be  gently  shaken  in  the  solution  from  time  to  time  during  its 
sensitization  The  bath  is  of  course  situated  in  the  dark-room, 
yellow  glass  being  a sufficient  protection  from  actinic  rays, 
even  of  day  fight,  and  the  “ wet-plate  dark  slide  ” is  placed 
ready  at  hand,  not  lying  fiat,  but  leaning  at  an  angle  against 
some  object.  A few  pieces  of  pure  filter  paper  should  also  be 
at  hand.  The  “ dark  slide  ” used  for  dry  plates  will  not 


24 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


answer  for  wet  plates,  in  tlie  latter  case  the  plate  must  rest  on 
pure  silver  wires,  or  glass  corners,  and  the  slide  mnst  he  wiped 
out  carefully  after  each  plate  has  been  removed  from  it. 

After  a certain  time  of  immersion  depending  on  the  tem- 
perature and  on  the  nature  and  condition  of  collodion  and  bath, 
but  varying  from  three  to  five  minutes,  it  will  be  seen  on  lifting 
the  plate  from  the  bath  that  the  greasy  or  streaky  appearance 
seen  when  the  plate  was  lifted  the  first  time  has  disappeared. 
When  this  is  the  state  of  affairs  the  plate  is  fully  sensitized, 
and  it  will  have  a film  opalescent  and  bluish  or  gray  according 
to  the  salts  used  in  the  collodion.  The  plate  is  lifted  slowly 
from  the  bath,  allowed  to  rest  one  end  for  a few  seconds  on 
several  plies  of  pure  filter  paper,  the  back  wiped  with  filter 
paper  ; and,  the  same  edge  being  carefully  kept  downward 
throughout,  the  plate  is  placed  in  the  dark  slide,  and  the  door 
of  the  slide  shut.  A piece  of  red  blotting  paper  may  with 
advantage  be  used  to  back  the  whole  plate  in  the  slide.  The 
slide  is  to  be  carried,  and  laid  down,  always  with  the  same 
side  downward ; the  solution  sure  to  accumulate  at  the  lower 
part  of  the  plate  must  never  be  allowed  to  run  back  over 
the  film. 

The  silver  bath  must  be  acid  in  reaction,  decidedly  acid  for 
our  special  work.  And  to  acidify  it  we  prefer  nitric  to  acetic 
acid.  A great  excess  of  acidity  makes  the  film  less  sensitive 
to  light,  but  we  must  have  a certain  amount  of  acidity  to 
ensure  clearness.  Fig.  3 shows  a “ dipping  bath,’’  if  a flat 
dish  is  to  be  used  it  should  be  of  glass.  The  “ dipper  ” in  one 
case  and  the  “ hook  ” in  the  other  should  be  of  silver. 

The  bath,  as  we  have  hinted,  is  liable  to  certain  diseases, 
and  is  sure  to  contract  one  or  other  in  time.  It  may  become 
supersaturated  with  iodine,  which  will  cause  transparent  spots, 
called  “ pinholes,”  and  this  may  be  cured  by  dilution,  filtra- 
tion, and  recuperation  to  original  strength.  Ether  and  alcohol 
from  the  collodion  will,  in  time,  find  their  way  to  a mischiev- 
ous extent  into  the  bath,  when  the  plates  will  be  streaky  and 
unevenly  sensitized  ; the  cure  for  this  is  to  heat  the  solution 
for  a time  to  about  140  degs.  Fahr.  Organic  matter  is  likely 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


25 


sooner  or  later  to  contaminate  the  bath,  and  fog  will  mar  the 
images;  to  cure  this,  neutralize  the  acidity  with  excess  of 
sodium  carbonate,  place  the  liquid  in  the  sun  for  some  days, 
filter  very  carefully  and  re-acidify  with  nitric  acid.  The  bath 
must,  of  course,  be  kept  up  to  strength,  to  test  which  a hydro- 
meter arranged  as  an  u argentometer  ” may  be  used.  When 
one  bath  is  undergoing  any  of  these  regenerating  processes, 
the  duplicate  previously  recommended  will  come  into  use. 

The  wet  collodion  process  is  practically  used  only  for  reduc- 
tion, or  at  least  copying  processes,  for  it  would  evidently  be 
awkward  to  make  a contact  slide  with  a wet  plate.  The 


Fig.  3. 


exposure  in  the  camera  must  be  found  out  by  experiment,  but 
copying  a negative  of  average  density,  reducing  to  one-third 
size,  lens  at  daylight  in  autumn,  fine  ground  glass  behind 
negative,  system  pointing  toward  sky,  chemicals  in  good  order, 
bath  fairly  acid,  we  find  an  exposure  of  about  90  seconds  is 
required,  using  the  iron  developer  given  on  page  27. 

After  exposure  in  the  camera,  the  plate  is  to  be  carried, 
with  precautions  as  before,  into  the  dark-room,  and  the  devel- 
oping solution  being  in  a cup  of  suitable  size  and  shape,  as  an 
egg-cup,  is  u swished  ” over  the  plate,  starting  at  the  edge 
which  was  uppermost  in  the  dark  slide.  This  application  of 
the  developer  differs  from  that  used  in  the  negative  process 


26  LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 

in  that  with  our  process  there  is  no  harm  in  sending  a small 
quantity  of  the  solution  beyond  the  edges  of  the  plate,  for  we 
not  want  any  great  density.  If,  however,  the  plate  has  been 
a long  time  in  the  dark  slide,  as  (say)  20  minutes,  it  is  better 
not  to  throw  overboard  any  considerable  quantity  of  the  solu- 
tion. Care  must  be  taken  that  the  accumulation  of  silver 
solution  at  the  lower  edge  of  the  plate,  if  contaminated  by  the 
wood  of  the  dark  slide,  be  not  allowed  to  run  back  over  the 
plate  so  as  to  cause  stains. 

We  formulate  two  developers,  the  former,  No.  1,  requiring, 
perhaps,  three  times  the  exposure  needed  for  the  second,  but 
No.  1 gives  the  better  results  in  our  opinion,  the  grain  of 
image  is  finer,  and  the  positive  is  usually  easier  to  tone, 
(see  later.) 


Pyrogallol 

Acetic  acid  (glacial) 
(Or,  Nitric  acid.  . 

"Water 

Alcohol 


No.  1. 

. 2 grains 

25  minims 

1 minim) 

1 ounce 

according  to  requirement 


The  pyrogallic  acid  may  very  well  be  dissolved  in  alcohol 
with  the  nitric  acid  added  to  preserve  the  pyro.  Thus : 

Pyrogallol 60  grains 

Nitric  acid 80  minims 

Alcohol . . to  li  ounce 

Of  this  solution  ten  minims  will  represent  one  grain  of  pyro, 
with  the  requisite  acid,  and  the  alcohol  will  probably  suffice 
unless  the  silver  bath  solution  be  very  much  used.  A new 
silver  bath  requires  practically  no  alcohol,  but  if  ever  the 
developer  runs  in  streaks  over  the  plate  alcohol  should  be 
added  to  the  developer  unless  indeed  there  is  too  much  alcohol 
in  it  already.  To  make  up  No.  1 with  pyro.  preserved  as 
above  we  take 


Pyro-alcohol  acid  solution, 
Water 


. . 20  minims 
to  1 ounce 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


27 


No.  2. 


Iron  protosulphate 12  grains 

Nitric  acid 1 minim 

Water to  1 ounce 

Alcohol q.  s. 


The  iron  may  be  used  in  larger  or  smaller  proportion,  but 
the  above  is  a good  average  for  temperate  weather.  The  iron 
solution  No.  2 and  the  alcoholic  pyro.  solution  of  No.  1 will 
keep  a fairly  long  time.  The  iron  salt  must  he  chosen  fresh, 
i.  e.  a good  green  color,  and  not  rusty-looking.  The  effect 
of  the  acid  is  to  make  the  developing  operation  slower, 
and  to  prevent  veil,  so  that  much  acid  either  in  bath  or 
developer  necessitates  longer  exposure.  If  the  pyro.  developer 
becomes  turbid  on  the  plate  it  must  be  rejected  instantly  and  a 
fresh  lot  applied.  The  developing  solutions  are  not  to  be 
poured  on  to  and  off  from,  the  plate,  but  kept  moving  steadily 
over  the  film,  and  they  must  not  act  too  long.  The  iron,  for 
instance,  ought  to  do  its  work  in  twenty  seconds,  the  pyro  will 
act  more  slowly.  The  appearance  of  the  plate  under  develop- 
ment is  our  best  guide  in  the  matter  of  exposure.  If  the  image 
flashes  up,  gray  all  over,  we  have  over-exposed  in  the  camera ; 
if  the  image  comes  reluctantly  and  strong  in  contrast  or 
refuses  to  appear,  or  is  very  weak  we  have  under-exposed.  If 
the  image  shows  a fair  amount  of  detail,  but  is  thin,  under- 
exposure is  the  probable  cause.  As  soon  as  the  developer 
seems  to  produce  no  more  effect,  or  as  soon  as  it  shows  signs  of 
becoming  muddy,  it  must  be  thrown  off  the  plate,  and  the 
plate  washed  in  water. 

Re-development  is  often  needed,  and  is  indicated  when  the 
density  obtained  by  the  first  development  is  insufficient. 
Re-development  consists  simply  in  a second  development  with 
the  help  of  a fresh  quantity  of  silver  nitrate  to  replace  what 
has  been  washed  off.  Take  half  an  ounce  of  the  original 
developing  solution  and  add  to  it  about  ten  minims  of  the  fol- 
lowing : 

Silver  nitrate  48  grains 

Nitric  acid 1 minim 

Water to  1 ounce 

Use  this  as  the  developer  was  used,  bewaring  of  turbid- 


28 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


ity  as  before.  If  the  plate  has  been  slightly  over-exposed  and 
is  full  of  detail  inclined  to  be  gray,  re-development  must  not 
be  practised,  but  rather 

Intensification.  After  the  plate  is  fixed  and  well  washed 
we  can  accentuate  such  details  as  are  already  developed,  by 
proceeding  exactly  as  for  re-development ; i.e.,  by  taking  some 
of  the  developing  solution  and  a small  quantity  of  acid  silver. 
Precautions  as  before. 

Fixing , or  Clearing.  To  remove  silver  haloids  not  reduced 
by  light  and  development  we  use  a solution  of  sodium  hypo- 
sulphite 1 part,  water  about  5 parts  ; or,  perhaps  preferably, 
potassium  cyanide,  20  grains,  water,  1 ounce.  (The  latter  salt 
is  very  poisonous,  even  by  absorption,  if  in  quantity.  If  by 
chance  cyanide  is  swallowed,  a dose  of  the  iron  developer,  or  of 
iron  sulphate  alone,  taken  immediately,  will  produce,  with  the 
cyanide,  an  insoluble  compound,  and  so  will  prevent  fatalities.) 
The  action  of  the  cyanide  must  be  watched,  the  operation  of 
clearing  being  carried  on  like  the  other  operations  of  this  pro- 
cess with  the  plate  on  a pneumatic  holder  or  similar  contri- 
vance. If  very  strong  the  cyanide,  especially  if  not  quite  pure, 
will  attack  the  liner  details  in  the  high  lights ; if  the  process 
be  watched  this  can  easily  be  prevented.  Hypo  has  less  ten- 
dency to  “ eat”  but  is  more  difficult  to  wash  out,  and  before 
intensification  the  fixing  agent  must  be  thoroughly  washed 
out. 

If  a finished  plate  after  washing  be  dried  before  a fire  it  will 
take  a little  more  density  than  if  dried  spontaneously. 

The  tone  of  a slide  produced  as  above  will  probably  be 
unsuitable  for  fulfillment  of  one  of  our  desiderata , but  a pyro- 
developed  plate  will  have  a tone  either  better  as  it  stands  or 
more  amenable  to  toning  than  an  iron  developed  slide.  To 
tone  either  one  or  other,  take 


Platinic  chloride  (PtCl4) 1 grain 

Nitric  acid 1 minim 

Water to  3 ounces 


Immerse  the  well  washed  plate  after  fixation  in  this  and 
watch  the  progress,  the  color  will  proceed  from  brown  onward 
to  nearly  black.  Palladium  chloride  may  be  used,  according 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


29 


to  Mr.  T.  X.  Armstrong,  in  the  same  way,  but  it  tones  more 
slowly,  and,  if  anything,  results  in  a warmer  brown  tone. 
Several  baths  of  the  platinum^  may  be  used  consecutively ; this 
is  found  a good  and  economical  practice  by  some  slide  makers 
of  commerce. 

Gold  may  also  be  used  to  tone  and  it  yields  a fine  warmth, 
notably  in  the  hands  of  certain  trade  slide-makers. 

The  writer  is  indebted  to  Mr.  Fred.  York,  perhaps  the 
largest  producer  of  lantern-slides  in  the  world,  for  the  follow- 
ing system  of  toning  lantern-slides  with  sulphur. 

Apply  to  therwashed  slide  a very  weak  solution  of  mercury 
bichloride,  but  do  not  let  the  film  bleach  at  all,  if  the  film  is 
allowed  to  turn  white  there  will  be  over-density  afterwards. 
Wash  the  plate  and  apply  a solution  of  potassium  sulphide 
(liver  of  sulphur)  2 drams  to  water  1 pint.  This  will  pro- 
duce a very  useful  tone ; a little  intensification  may  result,  but 
the  varnish  will  remove  the  superfluous  density. 

Collodion  plates  always  require  to  be  varnished,  for  the  film 
is  very  tender  and  liable  to  scratches  and  other  damage.  The 
varnishes  used  for  negatives  are  as  a rule  yellow,  and  so  not 
suitable  for  slides.  Yarnish  perfectly  white,  and  known  as 
u crystal  varnish,”  is  sold,  and  usually  good,  the  solvent  of  the 
gum  being  benzole  or  wood  naptha.  In  these  cases  the  var- 
nish is  applied  to  the  plate  cold,  the  application  being  after 
the  manner  of  collodionizing  a plate.  After  the  varnish  is 
thoroughly  dry  the  plate  is  to  be  cut  down  with  a diamond  to 
3J  inches  square,  and  mounted  as  directed  in  another  chapter 
(Chap.  XII). 

If  clear  varnish  is  not  procurable  the  following  formula  will 
be  found  to  answer : 

Amber  Varnish. 

Gum  amber  dissolved  in  chloroform — or  a less  costly  varnish  due  to 
Mr.  York. 

Sandarac 1 ounce 

Mastic ounce 

Benzole  20  ounces 

If  the  collodion  is  attacked  by  this,  flood  the  plate  with 
albumen  previously  to  varnishing. 


CHAPTEE  VI. 


Dry  Collodion  Processes. 

We  now  come  to  a set  of  processes  which  for  lantern-slide 
making  may  in  certain  respects  he  equalled,  but  cannot,  so  far 
as  we  know,  be  surpassed  by  any  photographic  process  at 
present  in  vogue.  For  camera-copying  purposes  these  pro- 
cesses with  dry  collodion  are  very  slow, 'especially  the  bath 
process  given  first,  but  in  proportion  almost  direct  to  their 
insensitiveness  they  endow  us  with  a power  of  getting  clear 
slides  and  of  modifying  the  tones  of  our  slides. 

No  person  can  claim  to  have  done  his  best  to  produce  per- 
fect slides,  unless  he  has  carefully  tried  the  effects  of  each  of 
the  processes  of  which  we  shall  give  examples. 

Collodion  Plates,  Bathed  and  Dried. 

After  a plate,  collodionized,  and  sensitized  in  a silver  bath, 
as  directed  in  last  chapter,  is  taken  out  of  the  bath,  it  may  be 
washed  in  distilled  water,  dried,  and  preserved  for  a certain 
time,  if  certain  steps  be  taken  to  prevent  the  pores  of  the  col- 
lodion from  completely  closing  up,  and  to  furnish  some  sub- 
stance to  absorb  the  halogens  when  exposure  and  development 
take  place.  The  substances  so  used  are  called  “preserva- 
tives” or  “ organifiers  ” technically.  The  plate  after  washing 
may  be  immersed  for  two  minutes  in  strong  coffee  (ground 
coffee  2 ounces,  boiling  water  10  ounces),  or  in  “fiat”  beer,  or 
in  a 12-grain  aqueous  solution  of  tannin,  or  in  equal  parts  of 
albumen  and  water.  After  this  immersion  the  plates  are 
simply  dried,  and  used  when  required.  The  collodion  may  be 
any  good  sample,  salted  as  in  last  chapter,  the  plates  must  be 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS.  31 

left  for  an  ample  time  in  the  sensitizing  bath,  perhaps  twice 
as  long  as  for  wet  plate  work.  The  developers  given  for  col- 
lodion emulsion  will  answer  for  these  dried  plates,  after  opera- 
tions as  for  wet  plate.  The  exposure  required  for  plates 
prepared  as  above  is  exceedingly  protracted,  in  fact  camera- 
copying is  well-nigh  out  of  the  question.  Not  less^  than 
twenty  times  the  exposure  for  wet  plates  will  be  needed  for 
these  dried  ones. 

Collodion  Emulsion  “ Unwashed.” 

Here,  in  place  of  forming  the  sensitive  salts  in  a film 
previously  containing  the  haloid  salts  only,  by  immersion  in  a 
silver  nitrate  bath,  we  form  the  sensitive  salts  in  the  collodion 
and  thereafter  coat  the  plate.  W e put  silver  nitrate  into  salted 
collodion,  whereby  at  once  an  emulsion  of  collodion  and  silver 
salts  is  formed,  but  also  there  are  formed  as  bye-products 
certain  salts,  useless  and  hurtful,  which  luckily  are  soluble 
in  water,  while  the  silver  salts  are  not  soluble  in  that 
liquid.  Moreover  we  require  to  dissolve  our  silver  nitrate, 
and  as  a considerable  quantity  of  water  would  spoil  our 
collodion,  and  would  not  mix  with  it,  we  dissolve  our  silver  in 
a very  small  quantity  of  water,  and  then  add  alcohol  to  it.  To 
get  rid  of  the  soluble  bye-products  we  wash  in  water  either  the 
whole  bulk  of  emulsion,  (“  washed  emulsion  process,”  page  33)  or 
each  plate  as  it  is  coated  (u  unwashed  emulsion  process.”)  With 
the  latter  we  now  deal,  and  our  formula  is  based  on  one  given 
by  Mr.  W.  B.  Bolton  some  years  ago.  We  have  tried  many 
formulae,  but  found  none  more  simple  or  efficient  than  this : 
Mix  3J  ounces  of  sulphuric  ether,  sp.  gr.  *720,  with  2 ounces 
(fluid)  of  alcohol  sp.  gr.  *820,  put  into  a stoppered  bottle  along 
with  36  grains  of  high  temperature  pyroxyline,  and  59  grains  of 
dry  zinc  bromide.  The  pyroxyline  must  be  fresh ; the  high  tem- 
perature samples  do  not  keep  well.  The  zinc  bromide  if  found 
damp  in  its  bottle  must  be  dried  before  it  is  weighed  out,  and 
if  the  sample  be  not  quite  pure  a slightly  larger  quantity  may 
be  used.  In  all  emulsion  work  accuracy  of  weighing  and 
measurement  is  essential  to  success.  The  pyroxyline  will  take 


32  LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 

some  time  to  dissolve;  the  bottle  should  be  shaken  once  or 
twice  at  first,  and  then  allowed  to  stand  still  for  a day  that  any 
sediment  may  settle.  The  clear  portion  is  to  be  decanted  off, 
care  being  taken  that  there  are  5J  ounces  of  the  clear,  for 
which  reason  an  extra  bulk  of  the  collodion  should  be  made 
at  first. 

Put  into  a test  tube 

Silver  nitrate.  . 

Distilled  water 

Boil. 

Put  into  another  tube  or  flask 

Alcohol  '820 6 drams 

Boil. 

While  both  are  boiling  pour  four  drams  of  the  alcohol  into 
the  silver  solution,  keeping  the  rest  of  the  alcohol  till  required. 
Take  the  bromised  collodion,  five  and  one-quarter  ounces,  the 
silver  solution,  and  the  small  quantity  of  alcohol,  into  the  dark 
room,  keeping  the  silver  hot ; and  then  pour  the  silver,  a few 
drops  at  a time,  into  the  bromised  collodion,  giving  the  collodion 
bottle  a violent  shaking  after  each  addition  of  silver.  When  the 
silver  tube  is  empty  wash  it  out  with  the  surplus  alcohol,  and 
pour  that  into  the  collodion,  shaking  strongly  for  a couple  of 
minutes.  The  previously  clear  collodion  will  now  be  like  so 
much  cream,  and  only  requires  to  be  set  aside  for  twenty-four 
hours  or  two  days  when  it  will  after  filtration  through  pure 
swan’s-down  calico,  or  medicated  cotton  wool,  previously 
moistened  with  alcohol,  be  ready  for  coating  plates. 

The  glass  plates  may  this  time  be  the  proper  size,  viz.,  31- 
inches  square,  and  they  must  be  cleaned  as  for  wet  collodion. 
Or  they  may  be  albumenized,  which  is  an  operation  we  do  not 
recommend  for  bath  processes.  Shake  up  the  white  of  an  egg 
with  40  ounces  of  water  containing  enough  liquor  ammonia  to 
cause  the  liquid  to  smell  distinctly ; let  stand  for  some  hours, 
then  filter  with  great  care.  To  albumenize  a plate,  clean  it 
with  soda  and  water,  wash  the  soda  entirely  off  under  the  tap, 
pour  the  albumen  solution  over  the  wet  plate  once,  throwing 


90  grains 
45  minims 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


33 


away  the  albumen,  and  again,  reserving  the  albumen  if 
desired,  but  filtering  into  a second  bottle.  Let  the  plate  dry. 
Or  the  plate  may  be  coated  with  a very  thin  solution  of  pure 
india  rubber  (or  Para  gum)  in  pure  benzole,  or  an  “edging”  J 
of  an  inch  wide  may  be  put  all  around  the  plate  with  a camel 
hair  brush.  Or  after  the  plate  is  cleaned  and  dried,  powdered 
talc  (French  chalk)  may  be  rubbed  over  it  and  then  rubbed  off 
till  none  is  visible,  but  this  rubbing  is  not  to  be  violent,  nor  to 
amount  to  polishing.  If  one  or  other  of  these  steps  be  not 
taken  the  film  will  leave  the  glass  during  after-operations. 
The  albumen  is  perhaps  the  “prettiest”  dodge,  and  the  solution 
improves  by  keeping  if  the  ammoniacal  smell  be  kept  up. 

The  plate  is  taken  on  a holder  and  coated  with  the  emulsion, 
evenly  and  steadily,  overflow  being  filtered  through  cotton 
wool  into  a second  bottle.  When  the  collodion  has  set  the 
plate  is  laid  in  a dish  of  distilled  water  for  one  minute,  then  it 
is  washed  in  common  water  till  greasiness  disappears,  then  it  is 
immersed  for  one  minute  in  coffee  as  on  page  30,  or  in : 


Bitter  Beer — 10  ounces 

Pyrogallol 10  grains 

Wash  the  plate  after  the  beer  but  not  after  the  coffee.  Put 
aside  to  dry.  This  emulsion  will  keep  for  a long  time,  but 
coated  plates  will  not  keep  nearly  so  well.  An  hour  before 
coating  plates  the  bottle  of  emulsion  should  be  well  shaken ; 


thereafter  it  is  to  be  kept  steady  until  coating-time.  With  a 
good  sized  bath  for  distilled  water  and  one  for  the  preservative, 
we  can  easily  coat  and  finish  3 dozen  plates  in  an  hour. 

Washed  Collodion  Emulsion. 

This  process  is  very  similar  to  the  last  up  to  a certain  point. 
W e form  an  emulsion  stronger  in  Pyroxyline  and  silver  salts, 
thus : 

Ether  .720 3^  ounces 

Alcohol  .820 2 ounces 

Pyroxyline 48  grains 

Zinc  Bromide 72  grains* 

Silver  Nitrate 120  grains 


* See  the  caution  regarding  purity  on  page  31. 


34  LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 

Emulsification  is  conducted  as  before,  and  the  emulsion 
ripens  in  from  48  to  60  hours.  Then  it  is  poured  out  into  a 
large  flat  perfectly  clean  glass  or  porcelain  dish,  and  allowed  to 
set.  As  soon  as  a skin  forms  on  top  it  is  broken  with  a silver 
or  ivory  implement,  so  that  the  solvents ' may  evaporate 
entirely.  Then  the  mass  is  broken,  or  cut,  or  torn  into  minute 
pieces  which  are  put  into  running  water  for,  say,  12  hours. 
We  put  ours  into  a tea  pot  of  earthenware,  tying  muslin  over 
the  lid-hole,  and  running  water  in  through  the  spout.  Then 
the  pellicle  is  collected,  squeezed  strongly  to  remove  water, 
and  kept  under  strong  alcohol  for  2 hours  at  least.  Then  it  is 
dried,  and  when  required  dissolved  thus  : 


Pellicle 20  to  25  grains 

Ether 4 drams 

Alcohol 4 drams 


Of  course  it  need  not  be  dissolved  until,  and  except  in  such 
quantity  as,  it  is  wanted.  The  plates  are  simply  coated  as  already 
directed  on  page  33,  and  allowed  to  dry,  slight  heat  to  acceler- 
ate drying  will  do  no  harm.  If  the  emulsion  becomes  after  a 
time  too  thick,  dilute  it  with  equal  parts  of  ether  and  alcohol, 
but  it  must  be  creamy,  not  milky.  The  emulsion  is  to  be 
shaken  one  hour  before  coating. 

Development  of  All  Dry  Collodion  Plates. 

The  exposure  varies  much  with  the  tone  aimed  at  and  con- 
sequently with  the  developer  used.  The  bath  process  is  very 
slow  even  at  its  quickest,  and  the  emulsion  plates  are  certainly 
three  times  as  slow  as  wet  collodion  even  at  their  best,  unless 
very  poor  tones  are  to  result. 

The  idea  of  the  developers  we  give  is  due  chiefly  to  Mr. 
Brooks,  of  Beigate,  who  is  a most  successful  producer  of  col- 
lodio-bromide  emulsions  for  slides,  and  of  slides  with  his  pro- 
duction. Those  whose  experience  is  limited  to  development 
of  wet  and  gelatine-bromide  plates  must  be  prepared  for  quite 
novel  phenomena  in  the  development  of  dry  collodion  plates. 
It  may  be  taken  as  a general  rule  that  wdth  dry  collodion  we 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


35 


develop  all  tlie  detail  first,  and  the  density  afterwards.  This, 
at  all  events,-  is  a description  that  will  not  lead  any  one  far 
astray ; if  any  one  finds  himself  getting  all  the  detail  on  his 
plate  without  density,  it  is  a mere  matter  of  time  to  get  the 
density  with  collodion  emulsion.  If  any  great  density  is 
acquired  before  all  detail  is  up,  we  may  be  sure  the  plate  is 
under-exposed  and  useless.  If  the  details  rush  up  hurriedly 
and  refuse  to  take  density,  we  have  over-exposed  and  our  best 
resource  is  to  wash,  fix  and  intensify. 

Before  developing  we  run  India  rubber  solution  round  the 
edges,  whether  the  plate  was  edged  or  albumenized  previously 
or  not.  W e may  hold  the  plate  on  a holder  in  the  hand  and 
pour  the  developing  solution  on,  or  we  may  put  the  plate  into 
a dish  and  develop  as  for  a gelatine  plate. 

The  longer  the  exposure,  counteracted  by  a restrained  devel- 
opment, the  warmer  will  be  the  tone  of  our  slide.  W e cannot 
get  a really  warm  tone  after  a sub-normal  exposure  ; if  we  use 
a heavily  restrained  or  a naturally  weak  developer  our  plate 
will  simply  be  under-exposed  ; if  we  use  a stronger  developer 
we  may  get  a slide  perfect  in  every  respect  but  the  tone, 
which  will  be  cold.  If  we  desire,  or  are  satisfied  with  cold 
tones,  we  shall  do  better  to  use  other  processes  more  rapid  and 
simple. 

The  first  step  towards  development  is  to  flood  the  plate  with 
equal  parts  of  methylated  spirits  and  water,  allowing  the  mix- 
ture to  act  on  the  film  for  about  thirty  seconds,  then  pour  it 
off  and  wash  the  plate.  This  step  is  to  be  taken  with  all  the 
collodion  emulsion  processes  we  give.  We  have  a great 
choice  of  developers,  each  one  tending  to  give  its  own 
particular  tone.  Ferrous  oxalate,  for  instance  (see  page  16), 
will  yield  a slide  quite  good  in  quality,  but  probably  cold  blue 
in  color. 

Mr.  W.  Brooks  uses  a developer  which  may  be  made  as  fol- 
lows : 

a.  Dissolve  96  grains  of  pyrogallol  in  1 ounce  of  absolute  alcohol. 

This  will  be  very  easily  done  and  requires  no  comment. 


36 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


b (1).  Ammonium  carbonate  ( saturated  solution).  ......  4 ounces 


Potassium  bromide 1 dram 

Sodium  acetate 2 drams 

Water 12  ounces 


To  prepare  the  solution  of  ammonium  carbonate  properly  is 
important.  The  carbonate  must  be  of  the  best  quality  and 
fresh,  the  crystals  clear  and  not  amorphous  ; if  there  is  around 
the  lumps  of  carbonate  a coating  of  white  amorphous  salt  the 
latter  should  be  pared  off  with  a knife,  as  it  not  only  does  not 
help  development  but  retards  it.  The  lumps  should  be  broken 
into  small  pieces,  put  into  a bottle  with  distilled  water  for 
some  days,  the  bottle  getting  a vigorous  shaking  occasionally. 

This  b used  with  a as  will  be  directed  presently,  gives  very 
beautiful  warm  tones,  as  fine  as  any  tones  that  can  be  produced 
by  any  purely  photographic  process.  But  by  wholly  or  partly 
replacing  the  ammonium  carbonate  by  sodium  or  potassium  car- 
bonate we  may  be  enabled  to  reduce  our  exposure,  though  at  the 
expense  of  a certain  amount  of  warmth  of  tone.  An  alkaline 
solution  (b\  of  which  we  are  very  fond,  gives  a fine  chestnut 


tone : 

<5  (2). Potassium  carbonate 800  grains 

Potassium  bi-carbonate 150  grains 

Potassium  bromide  60  grains 

Sodium  acetate 120  grains 

Water 12  ounces 


A mixture  of  this  and  b (1)  gives  a fine  tone  after  a fairly 
long  exposure.  Another  alkaline  solution,  b (3),  may  be  tried, 
it  yields  good  tones  of  less  warmth  than  those  already  given, 
but  the  tones  are  good  of  their  kind. 

b (8).  Potassium  carbonate 360  grains 

Potassium  bromide 60  grains 

Sodium  acetate 120  grains 

Water 12  ounces 

To  develop,  take  1 0 minims  of  a , mix  in  a measure  with  2 
drams  of  £(1),  or  b(2 ),  or  of  a mixture  of  b (1)  and  b(3),  and 
make  up  with  water  to  half  an  ounce.  The  plate  held  on  a 
pneumatic  holder  is  flooded  with  this,  and  the  solution  is  to  be 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


37 


left  on  the  plate,  moving  gently  over  it,  but  is  not  to  be  poured 
off  and  on.  This  is  our  own  method,  but  it  may  be  prefera- 
ble to  use  double  the  quantity  of  solution,  and  to  develop  in  a 
dish.  The  image  ought  to  appear  full  of  detail,  but  thin  at 
first,  and  to  gain  density  gradually.  With  b (1)  after  a proper 
exposure  the  development  ought  not  to  take  more  than  two  or 
three  minutes;  a considerable  amount  of  density  ought  to  be 
attained  before  development  is  stopped.  Experience  will  teach 
how  long  to  go  on. 

The  quality  of  the  slide  may  to  a considerable  extent  be 
regulated  by  the  quantity  of  a that  is  used.  A large  quantity 
of  a will  tend  to  give  brilliance  and  contrast,  a small  quantity, 
say  five  minims,  is  likely  to  give  harmonious  effects.  Mr. 
Brooks  uses  five  to  ten  drops  of  a and  three  drams  of  b (1). 

After  development  and  rinsing  under  the  tap,  fix  in  the 
ordinary  hypo.,  or  better,  with  a solution  of 

Potassium  cyanide 20  grains 

Water 1 ounce 

Remembering,  however,  that  the  cyanide  is  a strong  poison, 
toxic  even  by  absorption.  Wash  carefully.  If  the  slide  is  not 
as  clear  in  the  high-lights  as  desired  it  may  be  flooded  with  a 
solution  of  iodine  thus:  Tincture  of  iodine  (pharmacopoeia)  a 

few  drops  in  an  ounce  of  water.  Pour  this  on  and  off, 
especially  on  foggy  looking  parts,  for  a couple  of  minutes,  wash, 
then  apply  the  cyanide  solution  once  more. 

Intensification  is  apt  to  be  a dangerous  proceeding  with  a 
slide,  as  there  is  a tendency  to  block  up  shadows ; still  it  may 
be  performed  with  success  and  good  effect  thus:  After 

careful  washing,  after  fixing,  flow  over  the  plate, 


Pyro 2 grains 

Citric  acid 2 grains 

Alum  (common) 2 grains 

Water 1 ounce 


After  a few  drams  of  a solution  such  as  this  have  been 
poured  once  or  twice  over  the  plate,  add  a drop  or  two  of  a 
20  grains  solution  of  silver  nitrate  in  water,  acidulated  with 


33 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


citric  acid.  Pour  the  mixture  again  repeatedly  on  and  off, 
taking  care  to  avoid  over  density,  and  rejecting  the  solution 
at  once  if  it  becomes  muddy. 

To  tone  or  modify  the  warmth  of  a slide  which  happens  to 
be  too  warm  for  taste,  after  washing  immerse  in 


Platinum  chloride 1 grain 

Nitric  acid 1 minim 

Water 3 ounces 


till  the  desired  tone  is  obtained. 

To  produce  a beautiful  engraving  black,  highly  suitable  for 
copies  of  line  subjects : Tone  in  platinum  till  the  image 

almost  disappears  by  bleaching,  or  till  it  is  considerably  reduced 
in  strength,  wash  well,  and  intensify  with  the  pyro-silver 
solution,  from  which  the  alum  may  be  omitted. 

The  greatest  trouble  we  have  ever  found  with  this  process 
has  been  slipping  of  the  film  under  washing.  If  the  substratum 
be  properly  applied,  or  the  edging  before  coating,  and  before 
development  properly  performed,  slipping  ought  never  to 
occur.  At  the  same  time  we  must  not  use  the  plate  so  freely 
under  the  tap  as  if  it  were  a gelatine  plate. 

(For  a 66  printing-out  ” collodion  emulsion  process  see  page  59.) 


CHAPTER  VII. 


Gelatine  Bromide  Emulsion. 

This  process  for  making  slides  may  safely  be  called  tbe 
standard  process  of  the  present  day.  Gelatine  bromide  offers 
great  advantages  and  conveniences  on  account  of  its  sensitive- 
ness, and  if  proper  precautions  be  used  and  proper  measures 
resorted  to,  it  will  furnish  slides  which  will  bear  comparison 
with  any  slides  that  can  be  produced  by  purely  photographic 
methods.  But  to  utilize  its  convenience  we  must  not  allow 
ourselves  nor  our  plate-makers  to  neglect  the  precautions  nec- 
essary to  excellence.  Though  many  plate-makers  produce 
emulsion  fairly  well  suited  for  slide-making,  there  might  be 
improvement  in  every  case  we  have  yet  noticed.  We  are  pre- 
pared to  assert  that  gelatine-bromide  emulsion,  “slow”  though 
it  is  usually  made,  is  in  most  cases  not  slow  enough,  and  our 
experience  has  been  that  the  more  sensitive  have  been  the 
commercial  plates  we  have  used,  the  larger  our  percentage  of 
failures  or  only  mediocre  results.  The  slowest  emulsion  we 
have  ever  used  for  this  purpose  gave  us  the  best  series  of 
slides  on  gelatine-bromide  we  have  ever  made,  and  happily  as 
we  made  the  emulsion  ourselves  we  can  give  instructions  for 
its  production. 

Besides  over-rapidity  another  fault  is  often  found  in  com- 
mercial slide-plates,  viz. : the  use  of  an  unsuitable  gelatine. 
The  heavily  alumed,  or  hard  gelatines  seem  to  be  better 
adapted  than  softer,  purer  and  sometimes  alkaline  samples,  and 
our  experience  is  that  with  a hard  gelatine  there  is  less  ten- 
dency to  formation  of  scum,  due  partially  to  salts  in  ordinary 
tap  water,  than  with  a pure  soft  sample  such  as  Nelson’s  No. 
1.  Mr.  W.  B.  Bolton  prefers  the  softer  and  purer  gelatines  such 


40 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


as  Nelson’s,  and  his  dicta  are  worthy  of  attention.  He  insists 
on  the  use  of  distilled  water  throughout,  but  we  find  this 
unnecessary  if  we  use  our  acid  alum  finally.  Another  matter 
requiring  preliminary  notice  touches  the  haloid  salts  to  he  re- 
commended. There  is  no  doubt  that  a trace  of  chloride  in  the 
emulsion  tends  to  improve  the  color  of  the  image,  and  it  is 
difficult  to  see  of  what  advantage  an  iodide  is  likely  to  be  in  an 
emulsion  for  our  purpose,  still  the  fact  remains  that  the  fine 
emulsion  to  which  allusion  has  just  been  made  contained  iodide 
but  no  chloride,  and  we  need  hardly  say  that  we  will  herein 
give  the  result  of  frequent,  not  isolated  experiment  in  formu- 
lating a gelatine  emulsion.  W e shall  give  also  a formula  for  a 
very  slow  gelatin e-bromo-chloride  emulsion  which  will  work 
very  well,  and  may  suit  those  who  do  not  find  their  experience 
of  the  bromo-iodide  tally  with  ours. 

Gelatine-Bromo-lodide  Emulsion.  — Place  in  an  earthen 
ware  jar  having  a lid  : 

Gelatine  (soft,  as  Nelson’s  No.  1) 10  grains 

Potassium  bromide 70  grains 

Cold  distilled  water 5 ounces 

Soak  30  minutes. 

Heat  to  about  130  deg.  Fahr.,  stir  well  and  see  that  solution 
is  complete.  When  at  130  deg.  add  in  crystals,  silver  nitrate, 
90  grains.  This  of  course,  is  to  be  done  in  the  dark  room  by 
n on-actinic  light.  Yellow  glass  will  not  do  for  the  window 
when  gelatine-bromide  emulsion  is  in  use  ; the  medium  should 
he  clear  ruby  or  several  thicknesses  of  the  orange  colored 
fabrics  used  for  dark  room  windows.  The  emulsion  is  at  no 
stage  anything  like  so  sensitive  as  emulsion  used  for  negatives, 
but  it  is  certain  that  much  mischief  arises  from  the  worker 
taking  too  great  liberties  with  his  lighting  when  using  gelatine- 
bromide  plates  however  slow.  As  soon  as  the  silver  nitrate 
begins  to  dissolve,  which  will  be  immediately,  an  emulsion  will 
be  seen  to  he  formed,  and  the  liquid  is  to  be  stirred  and  kept 
warm  until  the  silver  is  all  dissolved.  Then  add  potassium 
iodide,  2 grains,  and  hydrochloric  acid  2 minims.  Cover  the 
jar,  place  it  in  a vessel  containing  hot  water,  and  boil  for  not 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


41 


more  than  five  minutes.  Cool  to  about  140  degs.  Fahr.,  then 
add  100  grains  hard  gelatine  — Heinrich’s,  or  Nelson’s  X 
opaque  — this  bulk-gelatine  may  be  added  dry,  stir  the  whole 
well  up  till  the  gelatine  is  entirely  dissolved,  then  cool  rapidly 
by  placing  the  jar  in  cold  water  or  even  iced  water.  The 
emulsion  should  set  in  a stiff  jelly,  and  is  ready  for  washing, 
unless  it  is  to  be  separated  by  centrifugal  action  which  we  con- 
sider preferable  to  washing  in  all  cases,  perhaps  specially 
preferable  in  slide  emulsion  making. 

Note. — For  a full  account  of  “ Separation,”  the  reader  is 
requested  to  refer  to  “Processes  of  Pure  Photography.”  If 
the  worker  proposes  to  separate,  he  will  use  in  the  original 
solution  of  gelatine  and  soluble  bromide,  20  grains  of  gelatine 
in  place  of  10,  and  after  the  boiling  he  will  cool  to  about  100 
degs.  Fahr.,  and  separate  briskly,  for  it  will  be  found  that  full 
time  and  force  must  be  allowed  for  separation  of  so  fine  an 
emulsion  as  this.  Having  poured  off  the  liquid,  if  the  drum 
is  a closed  one,  he  will  very  gently  rinse  out  the  drum,  and 
then  remove  the  silver  bromide  and  traces  of  gelatine  from  the 
sides  of  the  drum.  He  is  then  to  take  150  grains  of  hard  gel- 
atine, previously  swelled,  in  8 ounces  of  water  and  thoroughly 
incorporate  the  silver  bromide  with  the  bulk-gelatine  by  vigor- 
ous and  prolonged  stirring  and  heating  to  effect  solution  of  the 
gelatine.  When  solution  and  incorporation  are  complete  the 
emulsion  is  to  be  filtered,  cooled  and  set,  and  it  is  ready  for 
use  on  being  again  melted  by  heat. 

If  washing  is  to  be  performed  directions  are  given  for  the 
operation  a little  further  on.  (Page  43.) 

Gelatine-Bromo-Chloride  Emulsion. 

(See  “ Processes  of  Pure  Photography.”) 


Gelatine — Nelson’s  No.  1 30  grains 

Soak  in 

Water 3 ounces 

for  a few  minutes. 

Add 

Potassium  bromide 138  grains 

Potassium  chloride 20  grains 

10  per  cent,  dilution  of  hydrochloric  acid 12  minims 


42 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


Take  also 

Silver  nitrate 200  grains 

Water 3 ounces 

Put  the  gelatine  mixture  into  a flask  or  bottle  capable  of 
holding  at  least  12  fluid  ounces  and  heat  it  to  about  120  degs. 
Fahr.  Heat  also  the  silver  nitrate  solution  to  the  same  tem- 
perature, take  both  into  the  dark-room,  shake  the  gelatine 
into  a froth  and  then  pour  in  a few  drops  of  the  silver,  again 
shaking  well.  The  silver  is  to  be  added  a few  drops  at  a time, 
with  a hearty  shaking  after  each  addition,  finally  the  vessel 
that  contained  the  silver  is  rinsed  out  with  the  gelatine  mix- 
ture, and  a vigorous  shaking  for  a couple  of  minutes  completes 
the  emulsification.  The  emulsion  is  to  be  kept  at  about  140 
degrees,  for,  say,  an  hour.  It  must  not  be  boiled,  as  that 
would  make  it  too  sensitive,  but  the  operator  may  use  his  dis- 
cretion as  to  temperature  and  duration  of  digestion.  The 
longer  the  time  and  the  higher  the  temperature  the  more 
sensitive  and  the  more  inclined  to  fog  the  emulsion  will  be. 

For  emulsion  making  it  is  essential  that  the  chemicals  be 
absolutely  pure  and  the  weighing  out  accurate.  Even  when 
attempting  to  make  very  slow  and  “robust”  emulsion  for 
slides  we  got  violent  red  fog  on  several  occasions  by  using,  as 
we  afterwards  discovered,  an  alkaline  and  impure  sample  of 
potassium  bromide.  In  making  the  latter  emulsion  the  silver 
may  quite  well  be  added  in  crystals,  in  which  case  the  water 
used  in  our  formula  as  solvent  of  the  silver  nitrate  is  added  to 
the  gelatine  solution. 

After  digestion  we  must  get  rid  of  the  soluble  products  of 
decomposition — nitrates  chiefly — and  we  may  “ separate”  (see 
above)  or  we  may  “wash.”  If  we  are  going  to  wash  our 
emulsion  we  add  to  the  digested  bromo-chloride  emulsion,  at 
a temperature  of  about  130  degs.  Fahr.,  300  grains  of  a hard 
gelatine,  such  as  Heinrich’s,  previously  soaked  in  water,  the 
water  being  so  far  as  possible  squeezed  out  of  the  gelatine. 
After  tbis  bulk  gelatine  is  thoroughly  mixed  with  the  emulsion 
and  dissolved,  the  whole  is  cooled  rapidly  and  ought  to  set 
firmly.  It  is  then  cut  or  scraped,  with  silver  or  ivory  imple- 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


43 


ment,  out  of  the  vessel  in  which  it  set,  and  being  divided  into 
small  pieces  is  either  put  into  a bag  of  wide-meshed  muslin, 
or  into  a glass  or  ebonite  cylinder  having  a silver  gauze  or  net 
at  one  end  ; the  emulsion  is  forced  with  the  hand  through  the 
muslin  by  twisting  the  bag  up,  or  through  the  silver  meshes 
by  a u plunger,”  fitting  pretty  accurately  into  the  cylinder. 
The  end  of  the  bag  or  cylinder  is  held  under  cold  water  as  the 
jelly  is  squeezed  out.  The  shreds  of  jelly  may  be  received 
under  water  in  a hair  sieve  sitting  in  an  ordinary  hand  basin* 
water  is  run  into  the  basin  from  a tap  for  an  hour  at  least,  the 
sieve  being  occasionally  lifted  out  of  the  water,  or  a teapot 
may  contain  the  shreds,  water  running  in  by  the  spout  and 
the  lid-hole  being  covered  with  muslin.  The  best  article  we 
know  for  washing  in  this  way,  is  the  one  designed  by  Mr.  A. 
L.  Henderson,  its  strong  point  being,  besides  thoroughly  wash- 
ing the  emulsion,  that  it  can  be  used  in  daylight. 

Better  than  this  system  is  that  of  precipitation  by  alcohol. 
Three  or  four  times  the  bulk  of  alcohol  that  there  is  of  emul- 
sion is  placed  in  a large  jar,  and  the  emulsion  poured  in  a 
fine  stream  into  the  spirits,  with  constant  stirring.  The  clot 
is  to  be  removed,  cut  into  small  pieces  and  washed  in  running 
water  for  some  hours. 

After  washing,  the  shreds  of  gelatine  are  to  be  collected  in  a 
piece  of  muslin,  as  much  moisture  squeezed  out  as  pos- 
sible, and  solution  effected  by  heat.  Probably  9 or  10  ounces  of 
emulsion  will  be  found  to  result  from  this  treatment,  less  after 
the  alcohol  treatment;  a little  alcoholic  solution  of  thymol, 
enough  to  make  the  emulsion  smell  distinctly  of  the  latter,  will 
help  to  preserve  the  emulsion. 

If  we  separate  the  emulsion  after  digestion,  we  add  300 
grains  of  hard  gelatine  in  9 ounces  of  water  to  the  bromide 
left  in  the  drum,  and  we  add  an  ounce  of  alcohol  and  thymol 
solution  as  above. 

Filtering  gelatine  emulsion  is  most  easily  performed  by  use 
of  swansdown  calico,  previously  dipped  in  hot  water.  The 
gelatine  must  be  hot  during  filtration,  but  not  over  130  deg. 
Fahr. 


44 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


To  Coat  Glass  Plates  With  Gelatine  Emulsion. 

We  never  attempt  to  coat  plates  so  small  as  3J  inches  square, 
but  use  always  plates  6^x3J,  or  6^  inches  square,  cutting  them 
into  two  or  four  equal  parts  with  a diamond  and  a very  ingeni- 
ous arrangement  devised  by  Mr.  Cowan,  whereby  we  can  in 
the  darkest  of  dark-rooms  halve  a plate  without  trouble.  To 
clean  the  plates : rub  over  a new  plate,  previously  washed  under 
the  tap,  a cream  of  whiting  and  water,  and  let  the  cream  dry 
on  the  plate,  then  dust  it  oh  and  polish  the  plate  with  a clean 
soft  cloth. 

We  require  a leveling-slab  of  plate  glass,  slate  or  marble 
accurately  leveled,  and  having,  preferably,  thin  cords  or  piano- 
strings  stretched  tightly  over  the  top  of  the  slab  to  prevent  the 
plates  from  sticking  to  the  slab.  The  emulsion  at  about  100 
deg.  Fahr.  may  be  poured  onto  the  plate  almost  like  collodion, 
but  very  little  should  be  allowed  to  run  oh.  We  use  a silver 
ladle  which  holds  half  an  ounce  of  emulsion  and  is  provided 
with  a lip.  The  half  ounce  is  about  the  right  quantity  for  the 
6^-inch  square  plate,  for  we  do  not  require  a very  thick  film. 
As  soon  as  ever  we  have  got  the  emulsion  to  cover  the  plate 
either  by  tilting  the  plate  or  by  guiding  the  emulsion  over  it 
with  the  ladle  or  a glass  rod,  we  at  once  lay  the  plate  down  on 
the  level  slab.  When  the  emulsion  is  set,  which  depends  on 
the  temperature  and  gelatine,  but  ought  not  to  take  longer 
than  two  minutes,  the  plates  are  put  into  a drying-press,  or 
box.  The  requisites  for  drying  are : supply  of  fresh  air,  and 
removal  of  moist  air  from  the  vicinity  of  the  plates ; in  other 
words,  we  must  have  a constant  current  of  dry,  pure  air.  A 
room  is  the  best  drying  place,  if  we  can  arrange  to  leave 
and  enter  it  without  letting  actinic  light  reach  the  plates,  and 
dust  must  be  avoided.  (For  details  of  drying-boxes,  etc.,  see 
“ Processes,”  or  other  literature  dealing  with  gelatine-bro- 
mide processes.) 

The  plates,  when  once  dry,  may  be  put  in  boxes  or  in 
packets,  but  they  must  be  kept  in  a place  free  from  damp 
and  gaseous  emanations,  especially  from  house  gas. 


CHAPTER  VIII. 


Gelatine  Bromide,  Continued. 

Exposure  and  its  results.  With  the  wet  collodion  process 
whatever  exposure  we  may  give  we  shall  get  an  image  by 
development  of  a more  or  less  blue  color ; and  though  we  may 
by  well  executed  operations  make  the  color  a very  fine  blue- 
black,  or  real  black,  still  we  have  hut  little  range  of  color. 
But  with  emulsion  processes  in  general  we  have  always  a cer- 
tain range  of  colors  within  our  reach  ; dry  collodion  has  a very 
wide  range,  gelatine-chloride  also,  and  gelatine-bromide  prop- 
erly treated  is  not  far  behind  these  in  available  range  of  tone. 
An  exposure  much  longer  than  that  necessary  to  yield  full 
detail  with  the  ferrous  oxalate  normal  developer  may  he  fol- 
lowed by  a heavily  restrained  pyrogallol  development  with  the 
result  of  very  warm  tones  ; hut  a short  exposure  such  as 
requires  a fairly  powerful  developer  will  never  yield  warm 
tones,  never  at  least  has  done  so  in  our  experience.  If  we 
wish  warm  tones  we  must  give  a long  exposure  and  develop 
with  a heavily  restrained  or  naturally  weak  pyrogallol  devel- 
oper. Medium  tones  may  be  got  by  medium  exposure  and 
medium  strength  of  development. 

Several  systems  of  development  will  be  described  here,  and 
to  help  the  beginner  we  shall  suppose  that  the  exposure  (reduc- 
tion in  the  camera  by  daylight)  necessary  for  the  ferrous  oxa- 
late developer  as  formulated,  or  the  quinol  caustic  one,  is  one 
minute.  By  using  our  quinol-carbonate,  or  pyro-ammonia  or 
pyro-carbonate  developer,  medium  tones  will  be  obtained  after 
an  exposure  of  two  to  four  minutes,  and  the  use  of  our  pyro- 


46 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


and  carbonate  of  ammonia  developer  will  give  very  warm 
tones  after  exposure  of  from  eight  to  twelve  minutes.  The 
point  is  to  be  able  after  one  of  these  very  protracted  exposures 
to  avoid  fog. 

Ferrous  oxalate  developer,  which  will  give  good  but  cold 
tones  : 

a.  Iron  protosulphate 1 part  by  weight 

Water 4 parts 

Sulphuric  acid .1  dram  to  each  pint  of  the  above 

b.  Potassium  oxalate 1 part 

Water 3 parts 

Or  a cold  saturated  solution  may  be  kept,  the  bottle  being 
occasionally  shaken,  and  some  crystals  always  visible  at  the 
bottom. 

c.  Potassium  bromide % chemical  ounce 

Water  to 10  fluid  ounces 

The  developer : Pour  1 part  of  a into  5 parts  of  b,  and  for 
each  ounce  of  the  mixture  add  1 0 minims  of  c. 

Quinol-caustic  developer.  Cold  tones,  or  cold  medium. 


a.  Quinol  (or  hydroquinone) 80  grains 

Added  to 

Sodium  sulphite 1 ounce 

Citric  acid 30  grains 

Potassium  bromide 30  grains 

Water  to. . . 20  ounces 

Dissolved  together. 

b.  Potassium,  or  sodium  hydrate  80  grains 

Water  to 20  ounces 


The  developer  : Equal  parts  of  a and  b. 

The  water  of  b must  be  fresh  distilled,  or  ordinary  boiled 
for  ten  minutes. 

Quinol  carbonate  (Mr.  B.  J.  Edwards.)  Medium  tones : 


Sodium  sulphite 2 ounces 

Water  (hot) 20  ounces 

Quinol 30  grains 

Sodium  carbonate  (pure) 3 ounces 

Potassium  carbonate 3 ounces 

Potassium  bromide .40  grains 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


47 


This  may  be  made  up  in  two  solutions  which,  separately, 
will  keep  for  a long  time.  To  do  this  dissolve  the  sulphite, 
quinol  and  bromide  in  7 ounces  of  water,  the  remainder  in  13 
ounces,  or  6 and  14  ounces. 

Pyro-meta-bisulphite  developer.  (Mawson  & Swan.)  Warm 
or  cold  tones,  according  to  exposure.  A developer  of  great 


merit : 

a.  Pyrogallol 40  grains 

Potassium  meta-bisulphite 120  grains 

Water  to 20  ounces 

b.  Liquor  ammonia  fort 2^  drams 

Ammonium  bromide 40  grains 

Water  to 20  ounces 


The  potassium  salt  is  patented,  but  can  be  obtained  easily  in 
England.  As  we  always  use  it  for  preserving  our  pyro,  we 
give  our  ordinary  negative  formula,  but  for  warm  toned  slides 
the  “ meta  ” may  be  increased  three  times  at  least. 

Ordinary  negative  pyro  solution : 

Dissolve 

Potassium  meta-bisulphite 1 ounce  (avoir.) 

In 


Water 7 ounces 

Add 

Pyrogallol ...  1 ounce  (avoir.) 

Make  up  to 9 ounces  (fluid) 

Filter  and  label  “ Pyro.  10  per  cent.  10  minims  = 1 grain 
pyro.” 

If  we  make  up  ten  per  cent,  solutions  of  ammonia  and  bro- 
mide— thus : 


Liquid  ammonia  fort 1 ounce 

Water  to 10  ounces 

and 


Ammonium  bromide 
Water  to 


1 ounce  (avoir.) 
9 ounces  (fluid) 


48 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


we  may  make  a very  good  developer  for  slides  thus : 

Pyro  solution 15  minims 

Bromide  solution 20  or  30  minims 

Ammonia  solution 20  minims 

Water  to 1 ounce 


The  amount  of  bromide  to  depend  on  the  exposure.  The 
more  bromide  (restrainer)  our  exposure  will  allow  us  to  use  the 
warmer,  probably,  will  be  our  resulting  tone. 


Pyro,  ammonia,  and  ammonium 
(Thomas  & Co).  Por  warmish  tones, 

carbonate  developer 
but  must  be  used  with 

care. 

1.  Pyrogallol 

Sodium  sulphite 

Citric  acid 

Water 

2.  Liquor  ammonia 

Water 

3.  Ammonium  bromide 

Water 

4.  Ammon,  carb 

Water 

The  developer — for  warm  tones.  No.  1,  30  minims ; 
No.  2,  30  to  60  minims ; Nos.  3 and  4 each  60  minims ; water 
to  2 ounces. 

Pyro  and  ammonium  carbonate.  Warmest  tones. 

A.  Pyrogallol  as  Messrs.  Thomas’,  above. 

B.  Ammonium  carbonate,  fresh,  clear,  not  amor- 


phous crystals 1 ounce 

Water to  10  ounces 

The  developer : 

A . .10  minims 

B 2 drams 

Water to  1 ounce 

Bromide,  if  desired 3 4 Sra'n 


With  very  long  exposure  this  will  give  very  warm  tones, 
which  may  be  further  modified  by  the  acid-iron-alum  solution 
given  below. 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


49 


Finally,  mention  may  be  made  of  Mr.  Carbntt’s  Developer, 
which  we  have  used  with  satisfaction.  It  gives  a good  range 
of  tones. 

Car  butt’s  ferro-citro- oxalate  developer: 


A.  Potass,  oxalate 8 ounces 

Water 30  ounces 

Citric  acid 60  grains 

^Ammonium  citrate  solution 2 ounces 

B.  Ferrous  sulphate 2 ounces 

Sulphuric  acid 8 minims 

Water.  . . 32  ounces 

The  developer  is : 

A f 2 ounces 

B 1 ounce 

(Potass,  bromide,  if  desired *4  a grain) 


We  cannot  with  any  approach  to  accuracy  give  directions 
as  to  length  of  exposure,  but  having  already  taken  as  a hypo- 
thetic standard  one  minute  as  an  exposure  suitable  for  camera 
reduction  by  daylight,  we  may  now  say  that  for  contact-print- 
ing on  gelatine-bromide  plates  an  exposure  to  an  ordinary  gas- 
burner  of  12  seconds  at  10  inches  distance  may  be  a good 
starting  point  for  ferrous  oxalate  or  quinol-caustic  development. 
The  quinol-carbonate,  or  Thomas’  pyro-carbonate  and  ammonia 
developer  will  require  perhaps  30  to  50  seconds,  while  our 
ammonium  carbonate  as  the  only  alkali  will  require  for  warm- 
est tones  not  less  than  3 minutes.  Experiment  and  careful 
observation  of  results  alone  will  teach  the  proper  exposure  for 
this  as  for  all  other  photographic  operations.  Ho  matter  what 
developer  we  use,  if  our  image  rushes  up  rapidly,  thin  and 
veiled,  our  exposure  has  been  too  long ; on  the  other  hand,  if 
our  slides  are  wanting  in  half  tones  either  in  shadows  or  high 
lights ; if  they  have  black  and  white  in  close  juxtaposition  ; 
if  they  have  any  very  dense  or  opaque  parts  we  have  probably 
under-exposed.  We  can  say  no  more.  If  a slide  is  improperly 
exposed  the  only  sensible  step  to  take  is  to  make  another 
exposure,  no  dodging  of  development  is  ever  satisfactory. 

* The  ammonium  citrate  solution  is  made  thus  : Dissolve  1 ounce  of 
citric  acid  in  5 ounces  of  water,  add  liq.  ammonia  till  neutral,  then  make 
up  to  8 ounces. 


50 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


Manipulations  of  Development  are  so  simple  as  hardly  to 
require  notice.  The  plate  is  placed  film  upwards  in  a dish 
and  the  developing  solution  is  poured  quickly  over  it,  the 
plate  being  wetted  all  over  its  surface  at  once.  If  the  devel- 
oper is  weak  or  heavily  restrained  in  any  way  the  image  may 
not  begin  to  appear  for  a minute  ; the  Mawson  metabisulphite 
and  the  carbonate  of  ammonia  developers  take  at  least  a 
minute,  sometimes  more,  to  produce  any  visible  image. 
But  ferrous  oxalate  and  quinol  caustic  as  formulated  ought 
to  act  more  quickly  and  will  do  so  if  exposure  has  been 
sufficient.  With  some  developers  we  require  to  push  develop- 
ment further  than  with  others,  and  the  plates  used  make  a 
considerable  difference  in  this  respect.  But  in  all  cases  we 
must  not  stop  development  till  we  have  an  image,  seen  by 
transmitted  light,  considerably  denser  than  we  wish  the  final 
image  to  be.  The  ammonium  carbonate  developer  acts  in  a very 
curious  way  with  hard  tap  water,  a scum  seems  to  form  all  over 
the  plate,  but  disappears  on  fixing,  and  the  image  on  being 
washed  under  the  tap  before  fixing  becomes  decidedly  darker 
than  when  it  left  the  developer.  With  ferrous  oxalate  and 
quinol  developers  we  watch  first  the  shadows,  these  must  have  a 
certain  amount  of  density  if  the  slide  is  not  to  be  weak ; but 
sometimes  we  have  to  make  allowance — as  when  our  negative 
is  thin — for  fog  coming  over  our  highest  lights,  and  so  we 
may  have  to  stop  the  operation  before  the  shadow  details  are 
fully  up  to  our  standard  of  density.  It  must  be  remembered 
that  a slide  however  dense  may  easily  be  reduced  after  fixing, 
and  this  reduction  often  improves  a slide  in  other  ways  besides 
mere  general  reduction  of  density. 

When  development  is  judged  to  be  complete  the  plate  is 
washed  under  the  tap,  but  if  developed  by  ferrous  oxalate  or 
ferro-citro-oxalate,  it  should  get  two  or  three  rinses  in  water 
acidulated,  perceptibly  to  the  sense  of  smell,  with  acetic  acid. 
Citric  acid,  or  almost  any  acid  will  answer,  but  the  acid  is  to 
be  washed  out  before  the  plate  is  put  to  fix  in  the  hypo.  The 
acid  is  used  to  insure  elimination  of  the  iron  from  the  film. 

Scum,  likely  to  be  formed  by  combination  between  the  oxa- 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


51 


late  and  salts  in  tlie  water,  is  removed  easily  at  a later  stage. 
There  is  no  harm,  nor  any  use  that  we  know  of,  in  putting 
the  plate  into  alum  before  fixing,  hut  it  is  sometimes  recom- 
mended. The  beginner  must  not  trifle  with  his  light  for 
developing  bromide  plates ; one  thickness  of  yellow  fabric  is 
not  safe  ; we  know  that  many  slides  are  spoilt  by  carelessness 
in  this  matter. 

Fixing  Solution. 


Sodium  Hyposulphite 1 part 

Water 5 to  6 parts 


Must  not  he  acid,  and  the  plate  must  remain  for  ten 
minutes. 

Thereafter  wash  very  thoroughly,  unless  reduction  by  ferri- 
cyanide  is  to  be  practiced. 

It  may  be  taken,  as  a rule,  that  some  clearing  is  necessary 
with  most,  and  useful  with  all,  slides.  The  clearing  solution 
works  best  when  poured  onto  the  plate,  not  when  a dish  is 
used. 

C 

Solution  For  Clearing. 

Put  into  a large  bottle  some  alum  and  some  citric  acid  and 
add  water.  Alum  and  acid  are  always  to  be  visible  at  the 
bottom,  and  the  solution  should  be  shaken  or  stirred  now  and 
again.  To  use : take  four  ounces  of  the  supernatant  liquid 
and  add  one  dram  of  hydrochloric  acid,  pour  on  and  off  the 
plate  many  times  ; any  scum  there  may  be  will  be  dissolved  by 
this.  We  recommend  that  this  operation  be  never  omitted. 

In  order  to  clear  and  also  to  modify  the  tone  of  a slide  we 
use  a suggestion  of  Mr.  B.  J.  Edwards.  We  take  a clearing 
solution  as  above,  but  we  replace  one-half  of  the  acid-alum 
solution  by  an  equal  quantity  of  cold  saturated  iron  sulphate 
solution,  in  fact,  usually  by  the  iron  of  our  ferrous  oxalate 
solutions.  This  markedly  improves  the  tone  of  a quinol-caus- 
tie  slide,  also  that  of  a meta-bisulphite  or  quinol-carbonate 
slide,  but  it  has  a very  remarkable  effect  on  an  ammonium- 
carbonate  slide,  which  is  presumed  to  ha>  c already  a warm  brown 


52 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


tone.  The  solution  in  this  case  entirely  alters  the  color  of  the 
image,  and  by  graduating  the  amount  of  the  hydrochloric  acid 
and  of  the  iron,  we  can  go  through  a series  of  very  useful 
tones.  But  we  should  do  this  by  daylight,  for  hy  gas  light 
one  is  very  apt  to  overdo  the  action  and  produce  slides  of  a 
blue  that  may  almost  be  termed  ghastly.  The  author  puts 
forward  the  ammonia  carbonate  developer  followed  by  this 
clearing-toning  solution,  as  the  best  way  he  knows  to  get  really 
warm  tones  on  gelatine-bromide  slide  plates.  If  reduction  by 
iron  perchloride  is  to  follow,  the  iron-acid-alum  solution  is  to 
be  used  before  reduction  ; it  will  fail  after  it  probably. 

Reduction  of  Density , by  Potass.  Ferricy anide,  (or  Fer^ 
ridcyanide)  and  Hypo.  (Mr.  Howard  Farmer.) 

1st.  Lay  the  plate  in  fresh  sodium  hyposulphite  solution. 

2d.  Pour  into  a measure,  say,  2 drams  potass,  ferricyanide 
solution  10  per  cent,  in  water. 

3d.  Pour  the  hypo,  from  the  plate  into  the  measure  and 
pour  the  mixture  upon  the  plate,  but  be  careful  not  to  overdo 
the  reducing  action  which  will  start  at  once. 

Ho  iron  must  be  allowed  to  contaminate  the  ferricyanide 
solution ; If  this  occurs  a fine  green  will  follow  and  stain  the 
plate  almost  indelibly.  If  the  ferricyanide  itself  slightly  stains 
the  plate,  the  alum-acid  solution  — without  the  iron  — will 
remove  the  stain. 

By  Iron  Perchloride  and  Hypo.  (Mr.  Cowan.) 

Mix: 


Iron  perchloride  (pharmacopoeia  tincture) 2 drams 

Hydrochloric  acid 4 drams 

Water  to  20  ounces 


Place  the  plate  for  a couple  of  minutes  in  the  above,  then 
wash,  then  place  in  fresh  hypo,  solution  till  the  desired  effect 
is  obtained.  If  the  action  is  insufficient  repeat  the  operations. 
But  if  the  plate  not  freed  from  hypo,  be  placed  in  the  iron 
perchloride,  the  reduction  will  be  very  great,  even  to  danger 
of  spoiling  the  slide  entirely. 

If  there  is  occasion  to  make  slides  from  negatives  of  line 
subjects  such  as  engravings,  diagrams  and  the  like,  quinol  with 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


53 


a very  powerful  restrainer  will  yield  results  unsurpassed  by  any 
other  gelatine  process.  The  exposure  will  require  to  be  long 
and  development  will  be  very  slow  but  the  result  will  be 
absolute  clear  glass  and  opacity  and  an  absence  of  the  lateral 
development  which  so  frequently  spoils  line  images  on  gelatine 
plates. 

The  quinol  solution  may  be  made  thus : 

Quinol 40  grains 

Meta  bisulphite  of  potash 40  to  60  .grains 

Potass,  bromide 40  grains 

Water to  10  ounces 

Equal  parts  of  this,  and  a solution  as  follows : 

Sodium  or  potassium  hydrate. 80  grains 

Water to  10  ounces 

Twenty  minutes  may  be  required  for  development,  and  the 
dish  must  be  occasionally  moved  ; if  the  exposure  has  been 
right  the  result  above  mentioned  may  be  expected.  A similar 
developer  may  with  great  advantage  be  used  in  making  nega- 
tives of  line  subjects. 

Gelatine  slides  should  certainly  be  varnished  with  a clear 
varnish  such  as  will  be  found  mentioned  on  page  29.  Var- 
nishing clears  up  the  slide  considerably,  as  well  as  protecting 
the  film  from  damp  which  may  easily  occur  even  in  a mounted 
slide. 


CHAPTEK  IX. 


Gelatine-Chloride  Emulsion. 

The  following  is  a formula  given  a good  many  years  ago  by 
Mr.  Alex.  Cowan,  and  we  have  not  found  any  formula  more 
workable  or  more  satisfactory. 


a.  Sodium  chloride 48  grains 

Water 1 ounce 

b.  Silver  nitrate 96  grains 

Water 2 ounces 


Gelatine  (Nelson  No.  1 and  Heinrich  equal  parts).  .96  grains 

Soak  the  gelatine  in  the  water  of  a for  an  hour,  then  add 
the  chloride  of  a and  one  minim  of  hydrochloric  acid.  Melt 
the  gelatine  at  130  degs.  Fahr.,  take  into  the  dark-room  and, 
at  the  same  temperature,  add  b with  shaking.  Keep  at  130 
degs.  for  about  5 minutes.  Pour  into  a dish  to  set,  or  let  it 
set  in  the  original  vessel  if  the  latter  is  of  such  a shape  that 
the  jelly  can  be  easily  removed.  Break,  tear,  or  cut  it  up  into 
small  pieces,  or  shreds,  and  wash  as  for  gelatine-bromide  emul- 
sion (see  page  43).  The  coating  of  the  plates  is  also  to  be 
performed  as  for  gelatine  bromide,  but  a plate  coated  with  the 
chloride  emulsion  will  appear  much  more  transparent  than  one 
coated  with  bromide  emulsion.  In  fact  a plate  well  coated 
with  chloride  emulsion  is  so  transparent  and  the  film  so  glossy 
that  without  breathing  on  the  plate  it  is  often  difficult  to  tell 
which  is  the  glass  and  which  the  film  side.  The  glass  side,  of 
course,  will  u take”  the  moisture  of  the  breath  and  the  gelatine 
side  will  remain  undulled. 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


00 


In  all  processes  where  gelatine  is  used  for  slide  making 
distilled  water  alone  should  be  used  in  the  emulsion. 

The  exposure  with  such  an  emulsion  as  described  may  be 
made  by  contact  to  diffused  daylight  or  a few  inches  of  mag- 
nesium wire  or  ribbon  burned.  A medium  dense  negative 
may  require  5 to  10  seconds  to  diffused  daylight  for  warm 
tones.  As  with  most  other  processes  for  slide-making  a cold 
tone  may  be  obtained  with  a comparatively  short  exposure 
and  powerful  developer. 

MraB.  J.  Edwards’  Developer. — (Cold  tones). 


a.  Neutral  oxalate  of  potash 2 ounces 

Chloride  of  ammonium 40  grains 

Distilled  water 20  ounces 

b.  Sulphate  of  iron 4 drams 

Citric  acid.  2 drams 

Alum 2 drams 

Distilled  water 16  ounces 


Equal  parts  of  the  above  form  the  Developer. 

Mr.  A.  Cowan’s  Developers  for  Chloride  Plates.  (Examples.) 


No.  1. — (Cold  tones). 

Potassium  citrate 136  grains 

Potassium  oxalate 44  grains 

Distilled  water  (hot) 1 ounce 

No.  2. — (Medium  warm  tones). 

Citric  acid 120  grains 

Ammonium  carbonate 88  grains 

Distilled  water  (cold) 1 ounce 

No.  3. — (Warmest  tones.) 

Citric  acid 180  grains 

Ammonium  carbonate 60  grains 

Distilled  water  (cold) 1 ounce 


Three  parts  of  any  one  of  the  above  to  be  mixed  with  one 


part  of 

Proto-sulphate  of  iron 140  grains 

Sulphuric  acid 1 minim 

Distilled  water 1 ounce 


56 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


In  Nos.  2 and  3 above,  when  the  acid  and  the  alkali  are 
mixed  in  solution  there  will  be  considerable  effervescence,  so 
the  solution  or  mixture  should  be  performed  in  a larger  vessel 
than  is  required  to  hold  the  quantity  actually  made  up. 

A restrainer  is  sometimes  required  in  case  of  over-exposure 
or  thin  negatives,  in  this  case  a minim  or  two  of  a ten  per  cent 
solution  of  potassium  bromide  for  No.  1,  sodium  chloride  for  Nos. 
2 and  3,  may  be  added  to  each  ounce  of  developing  solution. 

Washing  and  fixing  are  as  for  bromide  plates. 

The  development  must  not  be  stopped  too  soon,  the  plates 
may  appear  fogged  after  a certain  amount  of  development,  but 
will  emerge  clear  from  the  hypo  solution.  Mr.  Cowan  even 
recommends  over-development  and  reduction,  after  fixing  and 
washing,  in  the  perchloride  of  iron  reducer  given  under 
gelatine-bromide  on  page  52. 

Gelatine-chloride  emulsion  produced  by  such  a formula  as 
we  have  given  may  be  made  much  more  sensitive  by  keeping 
hot  after  emulsification  for  some  hours,  or  even  by  boiling  for 
a few  minutes,  but  this  practice  we  cannot  recommend,  as  with 
chloride  there  is  much  risk  of  fog  in  such  cases. 


\ 


t 


CHAPTER  X. 


Henderson’s  Argentic  Stain.  — Transferotype  (Eastman.) 

By  a process  published  some  years  ago  by  Mr.  A.  L.  Hen- 
derson, and  us^d  experimentally  by  the  writer,  results  were 
obtained  more  decidedly  fulfilling  certain  desiderata  than  any 
other  process  we  have  ever  seen.  The  image  seems  really  to 
consist  of  a stain  rather  than  of  a molecular  precipitate  of  a 
metal,  but  of  course  it  is  a reduction  and  not  a stain.  The  pro- 
cess is  one  of  printing  out  and  subsequent  toning,  and  we  give 
it  as  a good  example  of  processes  which  might  be  classed  under 
that  one  head. 

No.  1. 

Soak  and  then  dissolve  at  low  temperature  : 

Gelatine 

In 

Water 

Add 

Sodium  acetate 

No.  2. 


Silver  nitrate 170  grains 

Water 10  ounces. 

No.  3. 

Sodium  citrate 80  grains 

' Sodium  chloride 20  grains 

Water ' 4 ounces 


Add  Ho.  2 to  No.  1,  then  add  No.  3,  all  the  solids  being  of 
course  dissolved,  and  the  temperature  low. 

Lastly,  add  2 ounces  of  dry,  hard  gelatine,  see  that  all  is 
dissolved,  make  up  with  water  to  30  ounces  and  coat  the  plates 
rather  thickly.  Dry  in  a drying  press  or  closet  in  the  usual 


240  grains 
10  ounces 
46  grains 


wav. 


58 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


Print  deeply  by  contact  in  daylight ; the  printing  will  be 
rather  slow.  Do  not  wash  the  plates  after  printing,  but  place 
them  directly  in  the  toning-bath  which  is  recommended  by 
Mr.  Henderson  as  follows  : 


Gold  chloride 2 grains 

Sodium  acetate 20  grains 

Sodium  chloride.. . . 20  grains 

Water  10  ounces 


Neutralize  the  acidity  with  chalk,  filter  out  the  chalk  and 
then  add  3 minims  of  acetic  acid. 

The  plate  is  treated  with  this  solution,  till  it  takes  a suitable 
tone ; it  will  go  through  various  changes  of  color  during  the 
operation,  and  the  longer  the  action  is  allowed  to  continue  the 
colder  will  be  the  tone. 

The  writer  toned  plates  produced  by  this  formula  with  the 


sulpho-cyanide  bath,  and  got  very  good  results. 

Ammonium  sulpho-cyanide ....  140  grains 

Sodium  phosphate 140  grains 

Sodium  tungstate 100  grains 

Water 24  ounces 

Dissolve  and  allow  to  stand  for  a day  or  two.  Then  add : 

Chloride  of  gold 15  grains 

Water 4 ounces 


This  bath  is  apt  at  first  to  act  unevenly,  especially  if  used 
too  new. 

After  toning  by  either  of  these  methods,  and  washing,  fix 
the  slides  in  weak  hypo,  thus : sodium  hyposulphite  1 part, 
water  10  parts.  Thereafter  wash  thoroughly,  dry,  and  varnish 
with  clear  varnish. 

A strong  point  of  this  process  is  that  combination  printing 
of  clouds,  etc.,  is  very  easy. 

Slides  on  Eastman  TransferotYpe  Paper. 

This  is  another  process  which  in  certain  cases  has  answered 
our  purpose  admirably.  By  the  Eastman  Company  of 
Rochester,  U.  S.  A.  paper  is  coated  first  with  soluble  gelatine, 
next  with  an  insoluble  emulsion  of  gelatine-bromide  of  silver. 
After  contact  printing  by  artificial  light  and  development 
usually  with  ferrous  oxalate,  the  paper  print  after  fixing  and 
washing  is  squeegeed  into  contact  with  a glass  plate  of  slide 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


59 


size.  After  a time  liot  water  is  applied  to  the  whole  and  the 
paper  comes  off,  leaving  the  positive  image  adhering  to  the 
glass.  After  very  careful  washing  in  hot  water  to  remove 
surplus  gelatine  the  plate  is  cleared  with  alnm  and  acid,  dried 
and  varnished.  Such  a slide  looks  much  better  on  the  screen 
than  might  be  expected  from  inspection  in  the  hand.  As  the 
Eastman  Company,  according  to  our  information,  do  not  pro- 
pose to  continue  the  manufacture  of  transferotype  we  need 
not  enter  fully  into  the  process. 

Collodio-chloricle  emulsion  furnishes  a very  fine  printing-out 
process  corresponding  in  collodion  to  the  argentic  stain  in 
gelatine.  This  process  was  worked  to  a considerable  extent 
many  years  ago  but  fell  into  disuse.  For  lantern-slides  it  is 
very  useful  and  the  process  is  simple.  We  have  just  lately 
refreshed  our  memory  by  making  some  of  the  emulsion, 
working  on  the  lines  given  in  the  u Year  Book  of  Photog- 
raphy, 1874.”  Dissolve  15  grains  silver  nitrate  in  15  minims 
of  boiling  water ; put  this  into  1 ounce  of  a good  sample  of 
plain  (unsalted)  collodion.  Then  add  in  yellow  light  3 grains 
of  calcium  chloride  dissolved  in  the  smallest  possible  quantity 
of  alcohol ; finally  add  1 grain  of  citric  acid.  In  making  this 
emulsion  the  usual  precautions  of  gradual  addition  and  shaking 
are  to  be  observed.  The  plates  albumen  ized  as  for  collodion 
emulsion  (page  32)  are  coated  with  the  collodio-chloride,  and 
when  set  are  dried  by  moderate  heat ; or  the  plates  may  be 
edged  with  albumen  or  india  rubber ; or,  previous  to  toning,  a 
tallow  candle  may  be  run  around  the  edges.  Print  very 
deeply,  wash  shortly  under  a rose  tap,  and  tone  in  any 
ordinary  toning  bath.  We  used  the  common  acetate  gold  bath. 


Sodium  acetate 25 

Gold  chloride  1 grain 

Water 8 ounces 


Kept  not  less  than  24  hours  before  use. 

The  image  leaves  the  printing  frame  in  a red  state  and  may  be 
toned  to  any  desired  color  attainable  by  gold  toning.  Fix  in  very 
weak  hypo  solution,  wash  under  a rose  tap,  dry,  and  varnish. 

This  process  is  well  worthy  of  trial ; like  the  argentic  stain, 
it  allows  of  easy  introduction  of  clouds,  etc. 


CHAPTER  XI. 


Coloring  .lantern  Slides. 

The  writer  has  to  confess  that  he  has  no  experience  in  the 
matter  of  coloring  slides,  and  that  he  is  nnable  to  discover  the 
beauty  or  advantage  of  painted  lantern-slides,  but  there  is 
no  doubt  that  well-colored  slides  are  popular  with  the  public, 
and  indeed  we  fear  it  must  be  acknowledged  that  many  of  the 
public  think  that  without  color  a slide  is  a very  poor  article. 
Children,  too,  are  very  partial  to  bright  colors,  and  for  the 
sake  of  the  little  ones,  if  for  no  other  reason,  we  propose  to 
devote  a chapter  to  slide-painting.  As,  however,  we  are  not 
personally  conversant  with  the  process  we  have  secured  the 
services  of  a friend  who  is  thoroughly  “ up  ” in  the  matter, 
and  whose  name,  had  we  permission  to  give  it,  would  be  suffi- 
cient guarantee  of  the  value  of  the  instructions. 

In  the  first  place  it  should  be  understood  that  the  slide  is  not 
to  be  varnished  ; if  the  positive  be  in  gelatine  no  treatment  is 
required ; if  it  be  collodion  the  film  should  have  a coating  of 
albumen. 

The  work  of  painting  on  a slide  is  by  no  means  so  easy  as  it 
might  appear  to  one  who  has  not  tried  it,  and  the  chief  diffi- 
culty is  the  mechanical  one  of  applying  the  pigments  to  the 
smooth  surface  of  the  picture.  Brushes  are  used  in  the  first 
place,  but  if  no  special  treatment  followed  their  use,  a painted 
slide  would  on  a screen  show  marks  of  every  hair  in  the 
brush. 

The  tints,  whatever  they  may  be  in  color,  must  of  course  be 
transparent,  and  so  we  are  limited  at  the  very  outset  to  choice 
of  only  a few  pigments  of  the  many  that  are  available  for 
ordinary  painting.  Water  colors  are  not  to  be  recommended 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


61 


for  our  work,  and  colors  for  the  purpose  of  painting  on  glass 
are  sold  by  some  dealers.  We  find,  however,  little  or  no 
difference  between  these  “special”  colors  and  the  ordinary 
oil-colors  sold  in  tubes  by  artists’  color  men.  Very  little  color 
goes  a long  way  on  a lantern  slide,  and  motives  of  economy 
should  not  prevent  us  from  buying  the  very  best  quality.  The 
following  list  of  transparent  pigments  will  probably  suffice  for 
all  requirements.  Reds : the  various  madders,  crimson  lake. 
Chinese  orange.  Yellows:  Italian  pink,  raw  sienna,  brown 
sienna.  Blue : Prussian.  Accessories : ivory  black  and 
McGilp.  f 

This  does  not  seem  a very  liberal  supply  of  pigments,  but 
it  must  be  remembered  that  very  many  tints  may  be  obtained 
by  judicious  mixture,  and  the  colors  we  have  named  are  con- 
spicuously transparent  and  so  suitable.  The  Ivory  black  is 
useful  in  compounding  certain  tints,  notably  “ neutral  ” tones. 
This  black  with  brown  sienna  and  a red  will  yield  a fine  warm 
brown,  with  brown  sienna  and  a blue  it  will  give  a fine  neutral 
grey.  Greens  are  to  be  obtained  by  suitable  admixture  of 
yellow  and  blue,  tempered  to  taste  by  other  colors. 

We  shall  require  a small  easel  to  be  kept  in  a sloping  posi- 
tion, and  it  should  have  a pane  of  clear  glass  as  a backing  for 
the  lantern  picture  which  will  rest  on  a bar  of  wood  stretching 
across  the  pane  of  glass.  In  fact,  a small  photographic 
retouching  desk  is  the  very  thing  needed.  A small  mahl- 
stick  and  a palette  will  be  required,  the  latter  may  be  of 
white  porcelain  and  should  be  kept  clean,  the  paint  being 
removed  from  it  with  a palette  knife  after  each  time  of  use, 
and  the  palette  being  then  cleaned  with  turpentine. 

Camel-hair  brushes,  and  a few  sables  such  as  are  used  by 
miniature  painters,  will  be  found  necessary.  Four  small 
phials  will  hold  the  following  : 

1.  Rectified  turpentine. 

2.  Canada  balsam,  ten  parts  ; turpentine,  one  hundred  parts. 

3.  Copal  varnish  and  turpentine,  equal  parts. 

4.  Japanner’s  gold  size. 

Further,  we  shall  need  a small  cup  or  pot  to  hold  turpen- 
tine, in  which  the  brushes  are  to  be  cleaned. 


62 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


The  easel  is  to  be  placed  near  a window  with  a good  steady 
light,  facing  north  by  preference,  in  a room  free  from  dust 
and  kept  at  moderate  temperature. 

Suppose  we  have  to  make  our  first  attempt  at  coloring  a 
slide,  and  let  us  suppose  the  slide  to  have  a sky  represented 
by  clear  glass.  A little  of  our  Prussian  blue  is  squeezed  out 
of  the  tube  (the  size  of  an  ordinary  grain  of  wheat  is  enough), 
by  its  side  on  the  palette  is  placed  a little  McG-ilp  ; the  brush 
wetted  with  turpentine  is  used  to  mix  a little  of  the  blue 
and  a little  of  the  McGilp  until  the  right  tint  is  produced. 
This  is  then  applied  in  even  strokes  from  side  to  side  on  the 
sky  of  the  slide  and  may  even  encroach  a little  on  the  land- 
scape. The  turpentine  is  allowed  a minute  to  evaporate,  and 
then  the  soft  pad  of  one  finger  is  used  to  dab  the  color  evenly 
all  over  the  sky  of  the  slide.  The  dabbing  must  be  kept  up 
till  the  effect  is  even  all  over,  and  the  softer  the  pad  of  the 
finger  the  better  the  result ; the  finger  may  be  rubbed  well 
with  pumice  stone  to  make  it  smooth.  This  operation  of  dab- 
bing requires  some  perseverance,  and,  we  need  hardly  say, 
some  practice  before  it  will  be  executed  to  perfection.  A few 
clouds  may  next  be  “ wiped  out  ” with  a piece  of  white  kid 
twisted  round  the  end  of  a penholder  or  small  stick,  the  posi- 
tion of  the  kid  must  be  frequently  altered  on  the  stick  so  as 
to  present  to  the  slide  a clean  surface  of  kid.  Distances  and 
shadows  may  be  next  filled  in  with  purple  made  by  mixing 
crimson  lake  and  blue,  and  these  masses  are  to  be  dabbed  as 
the  sky  was.  Next,  any  paint  that  may  have  gone  beyond 
the  intended  limits  may  be  wiped  off  with  the  kid,  and  then 
then  the  whole  plate  is  to  be  evenly  heated  before  a clear  fire, 
every  precaution  being  taken  against  dust.  The  heating 
makes  the  pigments  beautifully  transparent. 

After  about  an  hour  the  slide  will  be  dry,  and  the  rest  of  the 
painting  may  then  be  carried  out  with  a brush.  Dabbing 
cannot  be  executed  on  small  masses. 

Certain  colors  will  be  found  to  work  best  with  certain  media. 
Thus  the  reds  are  notoriously  slow  driers,  and  are  best  laid  on 
with  gold  size.  The  copal  mixture  will  do  for  most  of  the 


LAN  TERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


63 


other  pigments  ; but  Canada  balsam  may  be  found  best  adapted 
for  laying  on  the  yellows.  These  are  all  matters  for  experi- 
ment and  of  experience.  As  soon  as  the  painting  is  finished 
the  slides  should  be  mounted. 

Though  such  a matter  does  not  really  come  under  our  special 
subject,  we  may  give  a few  systems  of  drawing  diagrams  and 
designs  upon  glass  to  serve  as  lantern-slides. 

Dr.  Dallinger  produces  a very  fine  grain  on  glass  by  grind- 
ing two  pieces  together  with  emery  flower  and  water  between 
them.  He  then  draws  his  design  with  a pencil  on  the  ground 
surface ; the  design  is  colored  with  water  colors,  transparent 
ones  being  used.  Finally  the  slide  is  varnished  with  spirit 
varnish  which  obliterates  the  grain  produced  on  the  glass  by 
the  grinding.  If  it  is  found  that  the  colors  are  not  inclined  to 
be  smoothly  on  the  surface,  a little  treatment  of  the  latter  with 
ox  gall  will  set  matters  right. 

If  a glass  plate  be  licked  all  over  with  the  tongue  and 
allowed  to  dry,  a pen  and  ink  will  write  on  it  easily,  and  with- 
out running.  The  writing  may  be  strengthened  by  dusting 
over  the  plate  soot,  or  some  such  material.  After  such  treat- 
ment the  plate  will  stand  any  moderate  amount  of  rubbing 
without  losing  the  design  on  it. 


CHAPTER  XII. 


Masks — Mounting. 

When  a slide  has  been  varnished  all  that  remains  to  be  done 
is  the  choosing  of  a mask  and  the  mounting  of  the  slide  in 
such  a way  that  it  will  he  protected  from  scratches,  dust, 
atmospheric  influence,  etc. 

Cover-glasses  are  used  of  the  same  size  as  the  slides.  These 
covers  are  carefully  cleaned  with  spirits  and  ammonia,  or  with 
whitening  ; glasses  that  have  flaws,  as  scratches,  ridges,  bub- 
bles, or  strise,  are  to  be  rejected. 

As  to  masks.  The  best  and  most  convenient  are  white  on 
one  side  and  black  on  the  other ; the  white  is  suitable  for  bear- 
ing the  name  of  the  subject  and  also  for  showing  which  is  the 
front  of  the  slide.  TJntil  lately  the  apertures  cut  in  masks 
were  confined  to  a few  shapes  and  proportions,  nearly  all  bad. 
It  is  very  rarely  that  a circular  or  square  or  cushion  shaped 
aperture  of  standard  proportions  suits  the  composition  of  a 
picture  taken  on  an  oblong  plate,  and  clearly  a slide  ought  to 
carry  out  the  intention  of  the  artist  as  much  as  a paper  print. 
A gentleman  of  New  York,  we  believe,  first  called  public 
attention  to  the  shapes  of  mask  apertures,  and  much  improve- 
ment has  been  the  result.  Bor  ourselves  we  have  for  long 
used  masks  of  oblong  shape,  some  rounded  at  the  corners, 
some  not  so  ; oblong  apertured  masks  can  at  all  events  be  easily 
got  to  order  in  Britain  at  the  present  time.  The  price  of 
masks  seems  to  be  singularly  high,  and  it  will  repay  those  who 
use  many  masks  to  get  templates  made  of  proper  size  and  with 
suitable  apertures,  and  with  a Robinson’s  Trimmer  to  cut  out 
their  own  masks,  as  we  did  for  many  years. 

The  slide  is  laid  on  a table,  film  side  upward,  and  a mask  is 
laid  in  position,  white  side — if  any — uppermost.  A cover- 

glass  is  laid  on  the  mask,  and  the  whole  is  ready  for  mounting. 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


65 


There  is  great  variation  in  the  qualities  of  the  gummed 
strips  procurable  in  this  country.  Some  adhere  well,  some 
not  at  all ; some  are  too  thick,  some  too  thin,  some  too  wide, 
some  too  narrow.  Some  adhere  for  a long  time,  some  leave 
the  glass  very  soon.  The  fact  is,  that  most  of  those  who  make 
our  strips  have  no  practical  knowledge  of  our  requirements 
Still  good  gummed  strips  can  be  purchased.  They  should  be 
about  fourteen  inches  long  and  about  oneffhird  of  an  inch  wide ; 
not  so  thick  that  they  spring  away  from  the  glass  as  the 
slide  is  turned  over  in  process  of  mounting ; what  is  called 
“needle-paper,”  Answers  well.  We  believe  that  there  should 
be  some  sugar  in  the  mucilage  to  secure  adhesion  to  glass. 
When  we  wish  to  ensure  a very  long  life  to  our  slides  we  gum 
our  own  strips  with  thin  glue,  to  which,  at  the  suggestion  of 
Mr.  G.  W.  Wilson,  of  Aberdeen,  we  add  a little  oil  of  laven- 
der. A very  good  system,  recommended  to  us  by  one  whose 
name  we  unfortunately  forget,  is  to  mount  with  a thin,  porous 
paper  such  as  tissue-paper,  and  thereafter  to  dip  the  edges  of 
the  slide  in  a spirit  varnish,  such  as  shellac. 

The  operation  of  mounting  is  very  simple.  The  strip  being 
wet  except  one  inch  at  one  end,  and  laid  at  full  length  on  the 
table,  one  side  of  the  slide  is  pressed  down  at  one  end  and  in 
the  middle  of  the  breadth  of  the  strip,  the  slide  is  now  turned 
over  on  to  its  next  side,  the  corners  being  pinched  in  and 
turned  over  with  the  finger  and  thumb  of  the  free  hand. 
This  is  repeated  to  the  last  corner,  where  the  surplus  of  strip 
is  cut  or  sharply  pulled  off.  The  fingers  should  run  along  the 
sides  many  times,  and  care  should  be  taken  that  the  strip 
adheres  to  the  glass  at  the  ends  as  well  as  at  the  turn-over. 
This  entire  system  of  binding  slides  with  paper  is  bad,  and  the 
sooner  we  get  something  more  durable  and  equally  convenient 
the  better. 

The  slide  being  mounted  we  require  to  affix  some  marks  by 
which  the  lanternist  may  know  in  what  position  to  put  the  slide 
into  the  carrier.  In  Britain  the  generally  accepted  standard  is 
this : Lay  the  slide  as  the  picture  appeared  in  nature  or  is  to 

appear  on  the  screen,  then  place  a mark  at  each  of  the  two  top 
corners ; a white  mark  on  a black  mask  and  vice-versa. 


CHAPTER  XIII. 


Reduction  by  Artificial  Light.  Combination  Printing. 

Reduction  in  the  Camera  by  Artificial  Light.  With  mod- 
erately rapid  plates  this  may  he  managed  without  any  great 
trouble,  loss  of  time  or  expense.  The  cameras,  or  other  appa- 
ratus for  reduction,  are  arranged  in  the  usual  way  for  daylight 
reduction,  care  being  taken  not  to  stop  down  the  reducing 
lens  more  than  is  absolutely  necessary.  Magnesium  ribbon 
will  be  found  the  most  suitable  radiant  for  this  work.  The 
ground  glass  “ diffuser  ” behind  the  negative  may  be  used,  in 
which  case  the  magnesium — of  which  several  inches  will  be 
required — is  to  be  kept  moving  evenly  all  over  the  back  of 
the  ground  glass  as  near  to  it  as  convenient.  But  probably  a 
better  way  is  to  use  a reflector  such  as  a white  sheet  of  blotting 
or  filter  paper  placed  behind  the  negative  and  at  a suitable 
angle  to  it.  Two  pieces  of  magnesium  ribbon,  one  on  each 
side  of  the  reflector,  may  with  advantage  be  used,  and  the 
burning  ribbon  kept  moving  so  as  to  illuminate  all  parts  of 
the  reflector  evenly,  and  care  must  be  taken  to  guard  the  nega- 
tive against  direct  light  from  the  radiant.  An  “ illuminating 
box,”  such  as  lately  suggested  by  Mr.  T.  X.  Armstrong,  may 
be  found  useful  but  is  not  necessary.  The  light  given  off  by 
burning  magnesium  is  of  so  actinic  a character  that  the 
exposure  required  is  not  by  any  means  so  long  as  might  be 
expected. 

Combination  Printing , e.  g.,  of  Clouds.  A large  expanse 
of  clear  glass  representing  the  sky  over  a landscape  is  by  no 
means  an  artistic  or  pleasing  feature.  Clouds  may  be  printed 
in  on  the  following  lines,  but  the  operation  requires  consider 
able  skill,  care  and  experience,  and  in  the  most  accustomed 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


67 


hands  failure  is  not  uncommon.  Still  the  result  often  amply 
repays  the  trouble. 

1st.  A cloud  positive  may  be  printed  from  a cloud  negative 
by  contact  or  reduction  and  the  positive  used  as  cover  glass  for 
the  slide,  the  image-bearing  film  of  the  positive  being,  of 
course,  mounted  next  the  face  of  the  slide.  To  do  this  nicely 
by  contact  the  contour  of  the  horizon  of  the  positive  landscape 
should  be  traced  on  a piece  of  dark-colored  paper  and  cut  out, 
the  part  of  the  mask  representing  the  landscape  being  used  as 
a “vignetter”  for  the  clouds.  That  is  to  say,  a mask  corre- 
sponding to  the  landscape  is  to  be  held  in  front  of  the  frame 
and  quickly  moved  up  and  down  while  the  cloud  exposure  is 
going  on.  By  this  method  the  sky-blue  will  blend  nicely  with 
the  landscape  when  the  two  glasses  are  mounted  together. 
We  have  found  it  impossible  to  cut  away  or  dissolve  off  part 
of  a cloud  positive  so  as  to  make  it  fit  over  a landscape 
positive.  If  the  cloud  slide  is  to  be  made  by  reduction  the 
landscape  mask  must  correspond  with  the  landscape  of  the 
large  or  original  negative,  and  is  to  be  moved  slightly  behind 
the  larger  cloud  negative  during  exposure.  This  is  not  at  all 
an  easy  process.  If  it  is  found  that  the  clouds  encroach  on 
the  landscape  when  the  two  glasses  are  placed  together,  the 
lower  part  of  the  clouds  maybe  “reduced”  to  the  extent  of 
annihilation  by  potass,  ferricyanide,  or  iron  perchloride  and 
hypo.  As  these  can  be  used  with  a brush  the  cloud  sky-line 
can  be  nicely  graduated. 

2d.  Landscape  and  clouds  on  the  same  plate.  If  the  land, 
scape  and  cloud  negatives  are  both  of  the  same  size,  and  if  the 
cloud  negative  can  be  placed  exactly  where  the  landscape 
negative  was  during  reduction,  the  difficulty  in  cases  of  reduc- 
tion is  not  so  great  as  might  be  expected.  A print  of  the 
landscape  may  be  made  on  a sheet  of  spoilt  albumen  paper, 
for  instance,  and  only  deeply  enough  printed  to  show  the 
horizon  line.  We  then  cut  along  this  horizon  line  with  scissors 
and  preserve  the  two  pieces.  While  the  landscape  is  printing 
we  use  the  sky  mask  as  a vignetter,  and  when  the  cloud  is 
being  printed  we  use  the  landscape  mask  as  a vignetter.  In 


68 


LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


printing  by  contact  there  is  no  great  trouble,  and  in  reducing 
it  is  better  to  use  a larger  reflector  than  a diffuser,  for  the  hand 
can  get  between  reflector  and  negative  to  manipulate  the 
masks.  As  no  image  is  seen  we  must  take  care  to  “ register  ” 
the  positions  of  cloud  and  landscape  negatives.  In  reducing, 
our  routine  is  as  follows : Reduce  the  landscape,  shading  the 

sky — if  the  negative  sky  is  not  dark  enough — with  the  sky 
mask  ; shut  the  dark  slide ; put  cloud  negative  into  the  position 
lately  occupied  by  landscape  negative;  open  the  dark  slide 
and  expose  again,  shading  the  landscape  part  of  the  slide  by 
moving  the  landscape  mask  in  front  of  the  cloud  negative. 
These  are  somewhat  uncertain  operations,  but  with  care  and 
practice  they  will  produce  the  desired  effect. 


Table  for  Enlargement  and  Reduction. 


70  LANTERN-SLIDES  BY  PHOTOGRAPHIC  METHODS. 


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338 

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364 

14.6 

390 

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168 

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312 

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336 

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INDEX. 


PAGE. 


Acetate  Toner  Collodio-Chlo- 

ride 59 

Acidity  of  Silver  Bath 24 

Albumen  Preservative 30 

Albumen  Process 6 

Albumenizing  Glass 32 

Alum,  use  of  with  Gelatine.. . . 40 

Alum  and  Acid  Solution 51 

Alum  Before  Fixing  Gelatine 

Bromide 51 

Amber  Varnish 29 

Ammonium  Sulpho-Cyanide 

Toner 58 

Aperture  of  Reducing  Lens  . . 19 

Aperture  of  Masks 64 

Apparatus  for  Reduction 16 

Apparatus  Required 14 

Argentic  Stain,  Henderson's...  57 
Argentic  Stain  for  Shadows...  11 

Argentometer 25 

Armstrong,  His  Palladium 

Toner 29 

Armstrong’s  Illuminating  Box.  66 

Art  Considerations 8 

Artificial  Light,  Reduction  by.  66 
Author’s  Reducing  Camera. ..  . 18 

Beau  Ideal  Slid  es 5 

Beer  and  Pyro  Preservative.  . . 33 

Beer  Preservative 30 

Best  All-round  Process,  Gela- 
tine Bromide 13 

Bolton,  W.  B.,  His  Dry  Collo- 
dion Emulsion  31 

Bolton,  W.  B.,  On  Gelatines...  39 
Brooks,  Wm.,  His  Developers.  34 

Cameras  for  Copying 16 

Cam*  ra  Reduction 16 

Candle  Standard  for  Exposure.  14 
Carbutt’s  Developers,  Gelatine 

Bromide 49 

Centrifugal  Separation 41 

Character  of  Wet  Collodion.  . . 11 

Characteristics  of  Processes 


11  et  seq. 

Chloride  Emulsion,  Gelatine. . 54 

Chloride  in  Gelatine  Bromide.  40 
Cleaning  Glass  for  Wet  Collo- 
dion  22 


PAGE. 


“ Clear  ” Slides  and  the  Public  9 

Clearing  Gelatine  Plates 51 

Clearing  Solutions,  Gelatine 

Plates 51 

Clouds,  To  Print  in. 66 

Coating  Plates  with  Gelatine.  . 44 

Coating  with  Collodion  Emul- 
sion  33 

Coffee  Preservative  for  Dry 

Collodion 30 

Collodio-Chloride 59 

Collodion,  Iodized 22 

Collodion  Dry  Bath  Plates.  ...  30 

Collodion  Emulsion  . . . .31  et  seq. 
Collodion  Films  Slipping  ....  38 

Collodionizing  the  Plate 22 

Color  or  Tone  of  Slides 9 

Coloring,  Treatment  of  Slide 

for 60 

Coloring  Lantern  Slides 60 

Coloring  Slides,  Requisite  Ma- 
terials  61 

Colors  Suitable  for  Painting 

Slides 61 

Combination  Printing  of 

Clouds 66 

Contact  Printing,  Apparatus..  14 
Contact  Printing,  Distance....  15 
Contact  Printing,  Radiants  for.  14 

Copying  Engravings 53 

Cowan,  A.,  His  Gelatine  Chlo- 
ride Emulsion 54 

Cowan,  A.,  His  Plate  Cutter. . 44 

Cowan  A.,  His  Reducing  Pro- 
cess  52 

Cowan,  Mr.  A.,  His  Slides.  ...  19 

Cowan’s  Developers  for  Gela- 
tine Chloride 55 

Dallinger,  Dr.,  His  Designs  on 

Slides 63 

Dallmeyer’s  Lens  for  Reducing  19 
Damp  Attacking  Mounted 

Slides 53 

Dark  Slide  in  Wet  Process. ...  23 

Dark-room  Lanterns 15 

Deposite  in  Slide,  Nature  of...  7 

Description  of  Good  Slide. ...  7 

Developer,  Ferrous  Oxalate. . . 45 

Developer,  Pyro  for  Wet  Plates  26 


INDEX. 


PAGE. 


Developer,  Pyro-Meta-Bisul- 

phite 47 

Developer,  Quinol  Caustic.  ...  45 

Developers  lor  various  tones, 

gelatine  bromide 45  et  seq. 

Developers  for  Gelatine  Chlo- 
ride Plates 55 

Developing  Wet  Plates  25 

Development,  Manipulations  of  50 
Development  of  Dry  Collodion  34 
Dipping  Bath,  Wet  Process.  . . 23 

Distance  for  Contact  Printing.  15 
Dry  Bath  Collodion  Plates....  30 

Dry  Collodion 30 

Dry  Collodion,  Intensification . 37 

Dry  Collodion,  Organifiers . . . . 30 

Dry  Collodion  Plates,  Devel- 
oping   34 

Dry  Collodion  Plates,  Fixing..  37 
Dry  Collodion  Plates,  To  Tone  33 
Drying  Gelatine  Plates,  Coated  44 
Drying  Collodion  Plates 28 

Eastman  Co.  Tran sfero type ..  . 58 

Edging  Plates  for  Collodion 

Emulsion 33 

Edwards,  B J.,  Developer  for 
Gelatine  Chloride  Plates.  . . 55 

Edwards,  B.  J.,  Quinol  Devel- 
oper ...  45 

Edwards’ Clearing  Solution...  51 
Emulsifying  Gelatine  Emul- 
sion  41 

Emulsion,  Collodion  Washed.  33 

Emulsion,  Dry  Collodion 31 

Emulsion,  Gelatine  Bromo- 

Chloride 40-41 

Emulsion,  Gelatine  Bromo- 

Iodide 40 

Emulsion,  Unwashed  Collo- 
dion  . . 31 

Emulsion,  Washed  Collodion . 33 

Engraving  Black  Tones  on 

Collodion 38 

Engravings.  Copying  and  Mak- 
ing Slides  53 

Enlargement  and  Reduction 

Tables 69 

Essentials  for  Perfect  Slide 

7 et  seq. 

Exposure,  Relation  to  Develop- 
ment  49 

Exposure  of  Gelatine  Bromide 

Plates  45 

Exposure  of  Gelatine  Bromide, 
Results  of 45 


PAGE. 


Farmer,  Howard,’  His  Reducer  52 
Ferricyanide  Reducing  Process  52 

Ferrier.  His  Slides 6 

Ferro-Citro-Oxalate  Developer  49 
Ferrous  O palate  Developer. . . 45 

Filtering  Collodion  Emulsion.  32 
Filtering  Gelatine  Emulsion. . . 43 

Fixing  Dry  Collodion  Plates..  37 
Fixing  Gelatine  Bromide 

Plates 51 

Fixing  Wet  Plates 28 

Fog,  Red,  in  Gelatine  Emulsion  42 

Gas  Burner  for  Contact  Print- 
ing  14 

Gelatine  Bromide,  All-round 

Process 13 

Gelatine  Bromide,  Conven- 
ience of 39 

Gelatine  Bromide  Emulsion.  . . 39 

Gelatine  Bromide  Plates,  Ex- 
posure   45 

Gelatine  Bromo-chloride  Emul- 
sion  40 

Gelatine  Bromo-iodide  Emul- 
sion  40 

Gelatine  Chloride  Emulsion.  . . 54 

Gelatine  Chloride  Plates,  Ex- 
posure for 55 

Gelatine  Chloride  Plates,  Qual- 
ities of 12 

Gelatine  Chloride  Plates,  Re- 
duction  56 

Gelatine  Emulsion,  Alcohol 

Treatment 43 

Gelatine  Emulsion,  Coating  the 

Plates 44 

Glass,  To  Albumenize 32 

Glass,  To  Write  on  63 

Glass  for  Wet  Process,  Size  of  22 

Gold  for  Toning  Collodion 

Plates 29 

Good  Slide,  Description  of.  . . . 7 

Gradation  in  Slides 8 

Ground  Glass  for  Reduction. . . 17 

Ground  Glass  for  Slide  Camera  20 

Gummed  Strips 64-85 

Heinrich’s  Gelatine 42 

Henderson,  A.  L.,  His  Emul- 
sion Washer 43 

Henderson’s  A.  L.,  Argentic 

Stain.  ...  57 

Hydroquinone  Caustic  Devel- 
oper   45 

1 Hypo,  for  Wet  Plates 28 


INDEX. 


Inklsketch  on  Plain  Glass.  ...  63 

Intensification  of  Wet  Plates  . . 28 

Intensifying  Dry  Collodion..  . . 37 

Interiors,  Slides  of 9 

Introduction 5 

Iron  Developer,  Wet  Plates.. . . 27 

Lanterns,  Non-actinic 15 

Lantern,  Transferotype  Slides 

in  the 59 

Lens  for  Reducing,  Aperture  of  19 
Lens  for  Reducing,  Focus  of  . . 19 

Lenses  for  Reducing 19 

Level  Slab  for  Gelatine  Plate  . . 44 

Line  Subjects,  Engravings,  To 
Copy. 53 

Magnesium  Light  for  Reducing  66 
Magnesium  Ribbon  for  Expos- 
ure  15 

Magnesium  Ribbon  Spoiled  by 

Keeping 15 

Marking  Mounted  Slides 65 

Masks,  To  Make  at  Home  ....  64 

Mask  for  Contact  Printing 14 

Masks  for  Slides 10 

Masks  for  Slides. 64 

Mawson  & Swan,  Pyro  Devel- 
oper  47 

Mounting,  Operation  of 65 

Mounting  Slides 64-65 

Negatives  from  Line  Subjects..  53 
Nelson’s  Gelatine  for  Emul- 
sion  39 

Nested  Carriers  for  Negatives.  17 

Ocular  or  Eye  Piece  for  Focus- 
ing  20 

Oil  Lamp  for  Exposure 14 

Organifiers,  Dry  Collodion  ....  30 

Process,  Woodbury’s 5 

Process,  Albumen 6 

Printing  Frames  Required 14 

Process,  Wet  Collodion  21  et  seq. 

“ Pinholes”  Due  to  Silver  Bath  24 
Pinholes,  Cause  of,  in  Wet 

Process 24 

Pyrogallol,  Developer  Wet 

Plate 26 

Potass,  Cyanide  for  Wet  Plates  28 
Platinum  Toner  for  Wet  Plates  28 
Preservatives,  Dry  Collodion . . 30 

Pyroxyline  for  Emulsion  ....  31 

Pellicle,  Collodion  Emulsion.  . 34 


Precipitation  of  Gelatine  by 

Alcohol 43 

Packing  Gelatine  Plates 44 

Preservation  of  Gelatine  Emul- 
sion Plates 44 

Potass,  Meta-bisulphite 47 

Pyro  Solutions  for  Develop- 
ment   47 

Pyro  Ammonia  Developer.  ...  47 

Pyro  and  Ammonia  Carbonate. 

Developer 48 

Printing-Out  Slide  Process,  A . 57 

Paper  (Transferotype)  Slides. . . 58 

Paper  Strips,  System  Bad 65 

Printing-Out  Process  on  Collo- 
dion   59 

Printing  in  Clouds 66 

Palladium  Toner  for  Wet 
Plates 29 

Quantities  of  Good  Slides.  .7  et  seq. 

Quinol  Caustic  Developer 45 

Quinol-Carbonate  Developer. . 45 

Ramsden  Ocular,  To  Focus  ...  20 

Re-Development  of  Wet  Plates  27 
Red  Fog  in  Gelatine  Emulsion.  42 
Reducing  Camera,  Author’s...  18 
Reducing  Camera  Described..  . 16 

Reducing  Density  by  Iron 

Chloride,  Etc 52 

Reduction,  Requisites  for 16 

Reduction  and  Enlargement 

Tables 69 

Reduction  in  Camera 16 

Reduction  of  Density,  Gelatine 

Plates 52 

Reflector,  Angle  for  Reduction  17 

Reflectors  for  Reduction 17 

Regulator  Gas  Burner 14 

Requisites  for  Reduction ....  . 16 

Robinson’s  Trimmer 64 

Sandarac  and  Mastic  Varnish.  . 29 

Scale  of  Gradation 11 

Scale  of  Light  8 

Scientific  Slides,  Tone  for 10 

Scum  on  Gelatine  Plates 50 

Sensitizing  Wet  Plates 24 

Silver  Bath,  Acid 24 

Silver  Bath,  diseases  of 24 

Silver  Bath,  To  Iodize 23 

Silver  Bath,  Wet  Plate 23 

Size,  Convenient  for  Negatives  12 
Size  of  Slide 10 


INDEX. 


PAGE, 


Sketching  or  Writing  on  Plain 

Glass 68 

Sky  Negatives,  To  Print  in. . . . 66 

Slides  of  Line  Subjects 53 

Slides  to  Mark  for  the  Lantern.  65 
Slipping  of  Collodion  Films...  38 
Stand  for  Reducing  Camera. . . 19 

Strips,  Gummed 64 

Substratum  for  Collodion 

Emulsion 33 

Sulphur  Toning  Wet  Plates ...  . 29 

Swansdown  Calico  for  Filtering  43 

Tables  for  Reduction 69 

Tannin  Preservative 30 

Tap  Water,  Effect  of  on  Certain 

Plates 50 

Thomas  & Co.,  Pyro  Developer  48 
Tints  for  Coloring  to  be  Trans- 
parent   60 

Toning  Dry  Collodion  Plates.  . 38 

Toning  Wet  Plates 28 

Toning  Argentic  Stain 58 

Transferotype 58 


PAGE, 


Unwashed  Collodion  Emul- 
sion   31 

Varnish  for  Gelatine  Slides.  ...  5$ 

Varnish  for  Wet  Plates 29 

Warm  Tones 9,  12 

Washing  Collodion  Emulsion  . 34 

Washing  Gelatine  Emulsion. . . 42 

Wet  Collodion,  Character  of. . 11 

Wet  Collodion,  Qualities  and 

Dangers 21 

Wet  Process,  Exposure 25 

Wilson,  G.  W.,  His  Glue  for 

Strips 65 

Woodbury  Type 5 

York,  Mr.  F.,  His  Sulphur 

Toner 29 

York’s  Varnish  for  Collodion 
Plates 29 

Zinc  Bromide,  Purity  of 31 


44 


Sunlight  and... 

Shadow 

A Book  for  Photographers, 

AMATEUR  and  PROFESSIONAL. 


ft 


By  W.  X.  LINCOLN  ADAMS. 


Containing  Chapters  and  Illustrations  by  such  well-known  photographic  writers  and 

workers  as 

H.  P.  ROBINSON,  ALFRED  STIEGLITZ, 

A.  HORSLEY  HINTON,  R.  EICKEMEYER,  Jr., 

W.  B.  POST,  J.  WELLS  CHAMPNEY, 

B.  J.  FALK,  ALEXANDER  BLACK, 

W.  A.  FRASER, 

HER  GRACE  THE  DUCHESS  OF  SERMONETA, 
and  the  MARQUIS  DE  ALFARRAS. 


It  covers  the  field  entirely,  as  shown  by  the  fallowing 


(^!  CONTENTS  147) 


THB  CHOICE  OF  SUBJECT 
LANDSCAPE  WITHOUT  FIGURES 
LANDSCAPE  WITH  FIGURES 
FOREGROUNDS 
THE  SKY 

OUT-DOOR  PORTRAITS  and  GROUPS 
THE  HAND  CAMERA 


INSTANTANEOUS  PHOTOGRAPHY 
WINTER  PHOTOGRAPHY 
MARINES 

PHOTOGRAPHY  AT  NIGHT 
LIGHTING  IN  PORTRAITURE 
PHOTOGRAPHING  CHILDREN 
ART  IN  GROUPING 


About  150  pages  of  the  most  instructive  and  entertaining  reading  matter, 

....  and  .... 

More  than  lOO  Beautiful  Photo-Engravings, 


MANY  OF  THEH  FULL  PAGE  PICTURES. 


Printed  on  Heavy  Wood-cut  Paper,  with  liberal  margins  and  gilt  edges. 
Beautifully  and  Substantially  bound  in  Art  Canvas,  with  Gilt  Design. 


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60  and  62  East  Eleventh  Street,  New  York  City. 


ILLUSTRATIONS  IN  - 

Sunlight  and  Shadow. 


In  Prospect  Park  (Brooklyn).  .W.  I.  Lincoln  Adams. 

By  the  River A.  L.  Eidemiller. 

Morning  Mist H.  P.  Robinson. 

Day’s  Decline A.  Horsley  Hinton. 

Winter W.  H.  Dodge. 

The  Jungfrau Dr.  J.  Meiner. 

On  Lewes  Creek H.  Troth. 

Woods P.  Dementjeff. 

By  the  Stream E.  B.  Garrison. 

The  Jungfrau Alfred  Stieglitz. 

In  the  Highlands W.  Dawes. 

Landscape  and  Clouds Arthur  Burchett. 

Shades  of  Evening 

Her  Grace  the  Duchess  of  Sermoneta. 

Returning  from  Market Alfred  Stieglitz. 

An  English  Country  Scene..  .Seymour  Conway. 

Study  of  Fisherfolk Miss  K.  G.  Spink 

A Sicilian  Idyll Count  Von  Gloeden. 

Mending  Nets  (Katwyk) ...  . Alfred  Stieglitz. 

Here  Comes  Father Jesse  Poundstone. 

A Wet  Day  on  Boulevard Alfred  Stieglitz. 

Foregrounds — Fig.  1 H.  P.  Robinson. 

Fig.  2 

Fig.  3 

Fig.  4 

Fig.  5 

Fig.  6 

The  Sky— Fig.  1 

Fig.  2 

Fig.  3 

Fig.  4 

Fig.  5 

Fig.  6 

Hilltop  Farm W.  I.  Lincoln  Adams. 

A Gutach  Meeting Alfred  Stieglitz. 

Intimate  Friends Mabel  Osgood  Wright. 

An  Alpine  Cross Alex.  Keighley. 

As  She  Comes  Down  the 

Stairs R.  Eickemeyer,  Jr. 

“What  is  Your  Fortune,  My 

Pretty  Maid  . Major  R.  H.  Brown, 

“ Nobody  Axed  You,  Sir,” 

she  said “ “ “ 

The  Shepherd H.  K Noyes. 

“He  Cometh  Not,”  she  said..R.  Eickemeyer,  Jr. 

A Favorite  Occupation, 

Venice Alfred  Stieglitz. 

Winter,  Fifth  Avenue 

A Blockade,  New  York. . . . 

Wash-day,  Venice 

A Hot  Day 

In  the  Fields 

A Bit  Near  Munich 

A Venetian  Well 

A Venetian  Bit 


Venetian  Characters Alfred  Stieglitz. 

Katwyk  Beach “ 

Mid-ocean “ 

The  Diver Louis  Meld  on. 

Throwing  the  Hammer 

A Rise  in  the  World The  Marquis  de  Alfarras. 

The  Start James  Burton. 

Jumping  

A Snap  Shot C.  C.  Langill. 

A Reminiscence  of  Winter. . . W.  I.  Lincoln  Adams. 

Under  the  Willows,  “ “ 

A Country  Lane  in  Winter. ..A.  R.  Dresser. 

End  of  a Winter's  Day W.  B.  Post. 

Frost  Laden Randall  Spaulding. 

Boston  Public  Garden Newton  W.  Elwell. 

A Winter  Morning  in  Brookline 

A Rough  Morning Frank  Hurndall. 

Holy  Loch H.  P.  Robinson. 

Mr.  Gould’s  “Atlanta” 

Valkyrie  III,  Ailsa,  Britannia 

Sky  and  Sea 

Seagulls 

On  the  Heatherbell 

Marine  Study J.  M.  Bemis. 

Twilight,  Mid-ocean T.  Frank  Atkinson. 

The  Sea Harry  Platt. 

By  Bryant  Park  after  the 

Storm W.  A.  Fraser. 

The  Savoy  Hotel,  New  York 

—Stormy  Night 

Entrance  to  Central  Park 

The  Giant  Hotels,  from  Cen- 
tral Park “ 

Moonlight,  Central  Park 

Study  (from  Recollections  in 

a Mirror) J.  Wells  Champney. 

Portrait  Studies 

Isabel B.  J.  Falk. 

Minnie 

Rosita 

Rita 

Little  Tuesday 

Childhood 

Child  Study 

Reflections 

Child  Study Fred.  Boissonas. 

Art  in  Grouping — No.  1 

No.  2 

“ No.  3 

“ No.  4 

“ No.  5 

“ No.  6. 

Scene  from  “A  Capital 

Courtship” Alexander  Black. 


M Beautiful  Gift  Book  Tor  the  holidays. 

For  Sale  by  all  dealers  in  Photographic  Supplies,  Booksellers,  etc. 


PRICE,  POST  FREE,  IN  A BOX,  $2.50. 


“Amateur  Pnotograpiiy.'' 

: A : 

Practical  Guide  for  the  Beginner. 

by  W.  I.  LINCOLN  ADAMS, 

ILLUSTRATED. 

THIS  is  a practical  treatise  for  the  beginner,  by  one  whose 
experience  of,  and  immediate  contact  with,  the  needs 
of  those  who  are  using  the  camera,  in  and  out  of  doors,  both 
for  pleasure  and  profit,  especially  fits  him  to  help  the 

BEGINNER. 

CONTENTS: 

I. — Apparatus.  II. — In  the  Field.  III. — In  the  Dark-room.  IV. — 
Printing  and  Toning.  V. — Portraiture.  VI. — Instantaneous  Photog- 
raphy. VII. — Flash-light  Photography.  VIII. — Orthochromatic  or 
Color-sensitive  Photography.  IX. — Composite  Photography.  X. — 
The  “ Fathers  of  Photography.”  Appendix,  Tables,  Formulas,  Etc. 

THE  BOOK  IS  NOW  IN  ITS 

FOURTH  EDITION  and  FIFTH  THOUSAND. 

TOC/  CANNOT^  AFFORD  to  be  without  it. 

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